Hey all! I created my first DND character last year for my partner's campaign and it's been a huge blast. We're currently at Level 9, and I'm sitting at 8 levels of Vengeance Pally and one level of Hexblade Warlock. The Vengeance Paladin has been a lot of fun to play, and picking up that level of Warlock has added some really interesting utility and RP flavor. But since I find myself on the front-lines most often, I've been seeing my health get sapped repeatedly in only a couple of rounds, and my DM loves boss creatures with tough melee and some debilitating spells in their back pocket. I know Vow of Emnity is a beautiful combo with Hexblade's Curse to try and ensure a crit, but I've found myself losing turns to heal faster and faster, and have been eyeing the Oath of Ancients Aura of Warding feature to ensure getting a few more rounds in with resistance to spell damage that even affects allies within ten feet. I should also mention the campaign setting is literally a Wizard's Tower, so there seems to be a good chance of more and more spellcasters showing up in future sessions.
My character's RP backstory is he is a meathead Tiefling who swore an Oath of Vengeance with the Chaotic Evil Deity Beshaba, after his grad school class was slaughtered by their TA without fully thinking it through. He chose Beshaba on a whim because his line of Tieflings is descended from her, but began questioning why he chose his powers from an evil God. The Roleplay justification for switching Oaths would be he abandoned Beshaba after being offered Warlock powers by a mysterious Archfey, and is reflecting that he should perhaps adjust his personal Paladin Oath more towards a mission restoring balance to the world in general rather than glorifying his own personal need for vengeance.
Stats:
STR 14
DEX 10
CON 16
INT 10
WIS 10
CHA 18
Based on where I'm sitting at level wise, does it make more sense to just ride out Oath of Vengeance, or lose the delicious Vow of Emnity pick up the spell resistance from the Ancients Oath. I'm also thinking of taking a few more Warlock Levels, so if it really only synergizes well with the Vengeance Paladin, that would tempt me to stick with it. Let me know what y'all think and I appreciate it!
Oath of the Ancients can be really powerful since at higher levels casters have a tendency to become more common. Taking maybe 2 more warlock levels, or even just 1, is likely worthwhile for invocations and picking out a pact. With a few invocations your eldritch blast basically has the scaling of a longbow for fighter, though without the sharpshooter.
Are those stats rolled, or point buy? what kind of tiefling are you - generic or one of the variants? What do your ability score improvements and equipment look like? What is your combat style? What are your warlock spells known? And is there any chance your DM would allow you to make adjustments to things other than your oath?
If rebuilding is on the table, the first things I'd recommend are making sure your starting strength is at least a 15 (the required amount to wear plate armor - which you really should have by level 10 - without a movement penalty), and your combat style should be defense. Yes, it's the most boring combat style, but it scales the best and makes the biggest difference to your abilities relative to not having it. The damage boosts from dueling or great weapon style are nice when you get them, but as you level they're a less and less significant part of your overall damage output where +1 AC is always +1 AC.
Did you grab the shield spell with your hexblade level? it's kind of a big deal. Unfortunately you cast it while wielding a weapon and shield due to handedness issues. That leaves the best equipment options as:
1) prioritizing damage: wield a spear two handed, take the polearm master feat. advantages: don't have to worry about handedness while casting spells, extra bonus action attack and easily triggered reaction attacks to fish for crits to smite on. disadvantages: less AC due to not carrying a shield, dependent on wielding spears or quarterstaves specifically which means you can't use random magic weapons that the DM might drop.
2) prioritize tanking: wield any one handed weapon and a shield, take the sentinel feat. advantages: better concentration saves, cast booming blade as an opportunity attack, better AC due to carrying a shield, can use magic shields, can use any magic melee weapon you party finds as long as it's one handed and you have a night to rest and reset hex warrior. disadvantages: less damage due to lack of bonus action attacks - though between your channel divinity and hex warrior it's not like you're completely lacking in bonus action options.
Either way, your other ASI should be +2 charisma...
if getting beat up is an issue, I'd definitely lean toward the latter set up. That way, at level 10 with plate armor and a shield plus defense style you should have AC 21 that can be reactively bumped up to 26 with a reaction, both even higher if your DM has dropped magic armor or shields, which is high enough that you shouldn't be getting knocked around all the time. +4 charisma bonus and aura of protection is enough that save based attacks also shouldn't be that bad an issue.
...
If rebuilding is not an option, then go to your DM with the problem and ask if there's any way treasure loot might be tweaked to drop you some enchanted protection, say +1 chain and a +1 shield, or perhaps your patron might be open to you offering some sacrifice in exchange for a defensive boon, say +2 AC in exchange for some service or minor but interesting curse, or as a blessing in reward for some task that your DM might have it assign to you.
...
If oath change is allowed AND the only option available to you, then yeah, sentinel will blunt incoming spell damage a lot, but not weapon damage or spell effects, and its channel divinity and oath spells aren't as good as oath of vengeance - though you'll at least still have misty step, which is a pretty big deal for paladins given how limited their mobility can be.
I made this character a while ago but the stats were rolled, originally 16 CHA (14 w/ +2 Standard Tiefling Boost) and 14 CON and those are where I put my first two ASIs. I idiotically picked Protection Fighting because I built the character before I had ever played a session, so asking my DM to switch to Defense would be a very good call. My equipment setup is chain mail and sword-and-board for melee. I just got a Vorpal Longsword from an insane random loot drop last session so I see no reason to switch from that. I'll definitely take your advice to set up a more tanky build, because i usually find myself dashing for the biggest guy and soaking up as many hits as possible while spamming Vow of Emnity smites with advantage. I for sure picked Shield as my first Warlock spell, which already was extremely useful in the one session I've had it for so far, and my other level one spell is Id Insinuation, but may switch to Hex if I go the Ancients route and lose Hunter's Mark.
Even if I don't end up picking Oath of Ancients, this advice is all super helpful and I'll definitely be incorporating it! I seem to have the worst luck with spell saving throws even though Paladins are supposed to be build to withstand them, so the extra spell resistance insurance is super tempting but I love Vow of Emnity so much. The Vengeance spells are definitely cooler but I hardly find myself casting them and usually use the standard Paladin spells for utility purposes and let other casters handle debuffs in combat since I take too much damage to hold concentration anyway.
If I can't rebuild my stats, would you recommend prioritizing getting Sentinel or maxing out my CHA at the next chance? I'm pretty sure this campaign isn't going to go for a ton more levels so I don't want to be in a situation where the full potential will come out too far down the road, but I guess that's more a convo for my DM at the end of the day. Thanks again for all this I super appreciate it!
Sentinel is not a feat that makes you more survivable, it's a feat that makes the party more survivable by incentivizing the DM to attack you instead of your allies. If you're having problems taking too much damage or attracting too much attention, sentinel will make those problems worse. It's a fantastic feat for a tank not because it makes the tank tougher, but because it mitigates the main drawback of what you might call a 'turtle' build - one that prioritizes personal defense over everything else - ie, if the enemy can't hurt them they'll just ignore them to attack someone squishier, and the party will lose overall health resources faster rather than slower. If you're building a proper tank - like in the mmo sense of the word - sentinel is not only a good feat it's practically a must have (with a few exceptions - conquest paladins can make do without, particularly if they've taken the warcaster feat and dipped hexblade warlock for booming blade).
Anyway, I would not bother with sentinel, at least not for now. If you like Vow of Enmity and your character's lore & personality as a vengeance paladin, I'd say stick with it, and go to your DM with your issues.
A particular issue is the strength thing. 15 strength is kind of a big deal, at your level you should be rolling around in plate armor. Having 14 strength means being stuck in chain armor which is two whole points lower, and that's a lot of AC. The difference could be made up with item drops - gauntlets of ogre strength would do it, as would a +2 shield, or +2 chain armor, or +1 of both. However, asking the DM for a bunch of extra boons or magic items will probably be a hard sell considering you just picked up an amazing and extremely powerful magic sword - which, btw, congrats on that, vorpal swords are fantastic.
So items might be out. And ASIs aren't ideal, either. Like, you totally could take heavy armor master, picking up the point of strength to wear heavy armor and 3 points of damage reduction vs. non-magical weapon attacks. But that reduction doesn't scale and already isn't great at level 10, and only gets worse as damage increases and more enemies gain magical attacks of one form or another. And honestly, as a Hexadin your first ASI should be warcaster, and after that as many ASIs go to charisma as it takes to max it out. With the vorpal sword you could arguably eat the delay on to-hit and damage, but cha bonuses also apply to your spellcasting and, important given your problems, saving throws, so you'd really prefer not to.
Maybe ask your DM if you could make some sort of blood magic offering to your hexblade patron, sacrificing two points of constitution to gain two points of strength, effectively swapping your starting scores in these stats? Honestly if they let you trade two points of con for even just one point of strength I'd take them up on it. You'd definitely be paying a price, with lower stat modifiers overall, and lower health, in exchange for basically just the ability to wear plate armor, but imo that would be worth it, even given that reducing your max HP obviously isn't ideal if survivability is already an issue for you, but plenty of paladins make do on 14 constitution since the demands on their other stats are so high.
If the DM doesn't go for it though, then.... yeah, I probably would actually recommend either retraining one of your ASIs to Heavy Armor master, even at the cost of reducing your current charisma to 16, or taking it as your next ASI. Between that and retraining the combat style your AC will rise by 3 points, and if you're getting hit a lot then yeah that's worth it. At least for your character, it absolutely wouldn't be worth it for a conqueror or any other paladin multiclass that relies on offensive spells. After that, though, really, no more feats until your charisma is 20.
Now, saving throws. with +4 aura of protection, or even +3 if you retrain a +2 cha asi to heavy armor master, you should be pretty good, here? There's not a lot I can offer to help on this one, it sounds like you're maybe rolling bad. Actually, there is one thing. If you're going into a fight where you expect to be rolling a lot of saving throws, you should strongly consider sacrificing your first action to throw up Bless. Even at level 10, Bless is still a great spell, quite worthy of both your actions, spell slots, and concentration. Yeah, you'd probably prefer to be burning concentration on that fancy haste spell that oath of vengeance gives you, but if failing saves is a problem bless is a reasonable solution, and it also buffs to hit and applies to two other people, more if you up-cast it which you might have to do anyway if Shield is eating your first level slots. And the allies you do tag with it certainly won't be complaining. Sucks to give up a pair of attacks with a vorpal sword, but paladins are by design at least partially a support class, so sometimes your actions are going to go into support spells instead of smiting things. If you just wanted to hit things all day, you would have played a fighter or a barbarian.
With *at least* a +3 from aura of protection and +d4 from bless, even your bad saves should be somewhat reasonable. On average that's about what the more typical 'optimal' hexadin is bringing in with their +5 aura of protection at this level, and nobody accuses them of having bad saving throws. You'll still fail sometimes, but it shouldn't be a lot, and while it does eat your concentration, with advantage from warcaster you at least shouldn't lose the spell hardly ever.
Sadly, you won't be smiting much. Not when you want to reserve a couple 1st level slots per day for bless, and a few more for emergency castings of shield (which you should only break out if it'll make an attack miss AND you think that attack was going to do a lot of damage). That's probably going to be all your first level slots and maybe a couple of your second level slots as well, so you'll have a couple of BIG smites per day left over, but not enough to throw out a few in every encounter. It actually is probably worth your time to pick up at least one more level of warlock for that extra slot on a short rest timer. In my experience that should usually translate into two more spells per day, which goes a long way on a character with Shield and Bless. I wouldn't take it before your next paladin ASI at level 13, but maybe right after that. You could also pick up the fiendish vigour invocation which lets you start off most combats with 8 temporary hp. It's not much, but it helps.
Actually, the third level of hexblade would probably also be worth it for you, for the pact boon. The typical boon for hexblades is blade pact - but while stowing your fancy sword in a pocket dimension and summoning it whenever you need it is cool, you really don't need any of the blade pact invocations thanks to your vorpal longsword and already having extra attack. Instead, consider pact of the chain. An imp familiar would fit right in with your tiefling bloodline; is a useful little guy in general what with its grabby little hands, wings, and invisibility; and looks awesome as heck perched on your shoulder whether in imp or raven form, especially when you're in turn stacked upon your fiendish warhorse. It also would qualify you for the 'gift of the ever living ones' invocation from Xanathar's guide, which maximizes the dice of healing effects applied to you. That wouldn't make you take less damage, but at least would help you drain less resources from your party healer after the fight.
Actually, you might even go back into hexblade now and ride it all the way to the next asi. it would delay improved divine smite, which is a fair boost to your damage, but still.
If you ever do max out your charisma, consider putting whatever few ASIs you have left into inspiring leader. That's a ton of temp hp, not just for you but for your party as well. One dude with inspiring leader takes a lot of pressure of the party health reserves.
So, I guess, if we're rebuilding from the ground up, but not changing your starting stats or racial choice, I guess that's what I'd recommend.
starting stats: Strength 14, Constitution 16, Charisma 16 - not changing these just stating them for the record. Again ideally we'd like to bump strength up at least one point, even at the cost of sacrificing constitution, like if you could just straight up swap the two scores that would be better imo, but for now I'm assuming that isn't possible. level 1: paladin 1 level 2: warlock 1 - hexblade patron, booming blade, shield, whatever else you like level 3: paladin 2 - defense style level 4: paladin 3 - oath of vengeance level 5: paladin 4 - warcaster level 6-8: paladin 5-7 level 9: paladin 8 - heavy armor master (if your DM does let you swap your strength and constitution, then take +2 charisma here instead) level 10: paladin 9 - you should be here, with your vorpal sword picking up the slack for your primary stat which started good but is now falling a bit behind, wearing plate armor and carrying a shield, casting Bless whenever you expect incoming saving throws and Shield whenever it will stop you from taking a big hit. Your AC is 21 otherwise and your aura of protection grants a +3 to all saves for you and nearby allies. In tough fights you pop out Vow of Enmity and/or Hexblade's Curse and fish for crits - either insta-killing if you rolled a 20 or doubling a big third level smite if you critted on a 19 due to the curse. Your build maybe isn't "optimal" - but it should be perfectly functional, and you should be resiliant even in the face of the sorts of encounters 10th level parties go up against.
Future build looks maybe something like: level 11: warlock 2 - fiendish vigour, some other invocation level 12: warlock 3 - pact of the chain, imp familiar, retrain other invocation to gift of the ever living ones level 13: warlock 4 - +2 charisma level 14-15: paladin 10-11 level 16: paladin 12 - +2 charisma
Alternatively you do 3 levels of paladin first to get that tasty improved divine smite, and do the three levels of warlock after, both work fine. That puts you at level 16 with 20 charisma - a +5 bonus you apply to your attacks, damage, spells, and saves, significant improvements from your level 20 self before you even get into class features, including extra spell slots, higher spell slots, a fancy familiar, bonuses to healing both in terms of temp hp and maximized dice on healing effects, and an extra d8 damage on all your attacks from improved divine smite. Yeah there was an awkward period in the middle when your charisma was languishing a bit, but your amazing sword helped carry you through and by this point that's all in your past and you're ready to rock the final few levels of your progression hard. Hopefully you've picked up some magic armor or an enchanted shield, as you've basically tapped out the defensive boosts from class features, but even without you should be ok. And with a +5 aura of protection bless shouldn't be as necessary - though it remains a useful tool in your toolbelt and a good use of your 2nd level pact magic slots.
The last 4 levels of the build, assuming the campaign even gets that far, could be anything, really. 4 more paladin, picking up improved find steed for a fancy griffin or pegasus mount, would be pretty epic. Or 4 more hexblade levels, eventually picking up Shadows of Moil as a really great buff spell both offensively and defensively, plus some fun hexblade features like the ability to boss around the ghosts of enemies you kill. Or Maybe 4 levels of divine soul sorcerer picking up twin or quicken to use with haste. Or 4 levels of sword bard because bards are always cool. Or 4 levels of battle master fighter because action surge is a beastly ability at any level, and superiority dice give you another thing to tack on to hits, another way to profit extra from crits, and another short rest resource to ease the burden on your long rest spell slots. Regardless, at level 20 you get one final ASI, and can put it into inspiring leader, since by that point you should be champion famous across the realms. Granted you won't get much time to enjoy it, and the campaign probably won't get there anyway, but if you do it'll be a nice, party friendly hit point buffer to help you survive an epic capstone adventure.
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Hey all! I created my first DND character last year for my partner's campaign and it's been a huge blast. We're currently at Level 9, and I'm sitting at 8 levels of Vengeance Pally and one level of Hexblade Warlock. The Vengeance Paladin has been a lot of fun to play, and picking up that level of Warlock has added some really interesting utility and RP flavor. But since I find myself on the front-lines most often, I've been seeing my health get sapped repeatedly in only a couple of rounds, and my DM loves boss creatures with tough melee and some debilitating spells in their back pocket. I know Vow of Emnity is a beautiful combo with Hexblade's Curse to try and ensure a crit, but I've found myself losing turns to heal faster and faster, and have been eyeing the Oath of Ancients Aura of Warding feature to ensure getting a few more rounds in with resistance to spell damage that even affects allies within ten feet. I should also mention the campaign setting is literally a Wizard's Tower, so there seems to be a good chance of more and more spellcasters showing up in future sessions.
My character's RP backstory is he is a meathead Tiefling who swore an Oath of Vengeance with the Chaotic Evil Deity Beshaba, after his grad school class was slaughtered by their TA without fully thinking it through. He chose Beshaba on a whim because his line of Tieflings is descended from her, but began questioning why he chose his powers from an evil God. The Roleplay justification for switching Oaths would be he abandoned Beshaba after being offered Warlock powers by a mysterious Archfey, and is reflecting that he should perhaps adjust his personal Paladin Oath more towards a mission restoring balance to the world in general rather than glorifying his own personal need for vengeance.
Stats:
STR 14
DEX 10
CON 16
INT 10
WIS 10
CHA 18
Based on where I'm sitting at level wise, does it make more sense to just ride out Oath of Vengeance, or lose the delicious Vow of Emnity pick up the spell resistance from the Ancients Oath. I'm also thinking of taking a few more Warlock Levels, so if it really only synergizes well with the Vengeance Paladin, that would tempt me to stick with it. Let me know what y'all think and I appreciate it!
Oath of the Ancients can be really powerful since at higher levels casters have a tendency to become more common. Taking maybe 2 more warlock levels, or even just 1, is likely worthwhile for invocations and picking out a pact. With a few invocations your eldritch blast basically has the scaling of a longbow for fighter, though without the sharpshooter.
Are those stats rolled, or point buy? what kind of tiefling are you - generic or one of the variants? What do your ability score improvements and equipment look like? What is your combat style? What are your warlock spells known? And is there any chance your DM would allow you to make adjustments to things other than your oath?
If rebuilding is on the table, the first things I'd recommend are making sure your starting strength is at least a 15 (the required amount to wear plate armor - which you really should have by level 10 - without a movement penalty), and your combat style should be defense. Yes, it's the most boring combat style, but it scales the best and makes the biggest difference to your abilities relative to not having it. The damage boosts from dueling or great weapon style are nice when you get them, but as you level they're a less and less significant part of your overall damage output where +1 AC is always +1 AC.
Did you grab the shield spell with your hexblade level? it's kind of a big deal. Unfortunately you cast it while wielding a weapon and shield due to handedness issues. That leaves the best equipment options as:
1) prioritizing damage: wield a spear two handed, take the polearm master feat. advantages: don't have to worry about handedness while casting spells, extra bonus action attack and easily triggered reaction attacks to fish for crits to smite on. disadvantages: less AC due to not carrying a shield, dependent on wielding spears or quarterstaves specifically which means you can't use random magic weapons that the DM might drop.
2) prioritize tanking: wield any one handed weapon and a shield, take the sentinel feat. advantages: better concentration saves, cast booming blade as an opportunity attack, better AC due to carrying a shield, can use magic shields, can use any magic melee weapon you party finds as long as it's one handed and you have a night to rest and reset hex warrior. disadvantages: less damage due to lack of bonus action attacks - though between your channel divinity and hex warrior it's not like you're completely lacking in bonus action options.
Either way, your other ASI should be +2 charisma...
if getting beat up is an issue, I'd definitely lean toward the latter set up. That way, at level 10 with plate armor and a shield plus defense style you should have AC 21 that can be reactively bumped up to 26 with a reaction, both even higher if your DM has dropped magic armor or shields, which is high enough that you shouldn't be getting knocked around all the time. +4 charisma bonus and aura of protection is enough that save based attacks also shouldn't be that bad an issue.
...
If rebuilding is not an option, then go to your DM with the problem and ask if there's any way treasure loot might be tweaked to drop you some enchanted protection, say +1 chain and a +1 shield, or perhaps your patron might be open to you offering some sacrifice in exchange for a defensive boon, say +2 AC in exchange for some service or minor but interesting curse, or as a blessing in reward for some task that your DM might have it assign to you.
...
If oath change is allowed AND the only option available to you, then yeah, sentinel will blunt incoming spell damage a lot, but not weapon damage or spell effects, and its channel divinity and oath spells aren't as good as oath of vengeance - though you'll at least still have misty step, which is a pretty big deal for paladins given how limited their mobility can be.
I made this character a while ago but the stats were rolled, originally 16 CHA (14 w/ +2 Standard Tiefling Boost) and 14 CON and those are where I put my first two ASIs. I idiotically picked Protection Fighting because I built the character before I had ever played a session, so asking my DM to switch to Defense would be a very good call. My equipment setup is chain mail and sword-and-board for melee. I just got a Vorpal Longsword from an insane random loot drop last session so I see no reason to switch from that. I'll definitely take your advice to set up a more tanky build, because i usually find myself dashing for the biggest guy and soaking up as many hits as possible while spamming Vow of Emnity smites with advantage. I for sure picked Shield as my first Warlock spell, which already was extremely useful in the one session I've had it for so far, and my other level one spell is Id Insinuation, but may switch to Hex if I go the Ancients route and lose Hunter's Mark.
Even if I don't end up picking Oath of Ancients, this advice is all super helpful and I'll definitely be incorporating it! I seem to have the worst luck with spell saving throws even though Paladins are supposed to be build to withstand them, so the extra spell resistance insurance is super tempting but I love Vow of Emnity so much. The Vengeance spells are definitely cooler but I hardly find myself casting them and usually use the standard Paladin spells for utility purposes and let other casters handle debuffs in combat since I take too much damage to hold concentration anyway.
If I can't rebuild my stats, would you recommend prioritizing getting Sentinel or maxing out my CHA at the next chance? I'm pretty sure this campaign isn't going to go for a ton more levels so I don't want to be in a situation where the full potential will come out too far down the road, but I guess that's more a convo for my DM at the end of the day. Thanks again for all this I super appreciate it!
Sentinel is not a feat that makes you more survivable, it's a feat that makes the party more survivable by incentivizing the DM to attack you instead of your allies. If you're having problems taking too much damage or attracting too much attention, sentinel will make those problems worse. It's a fantastic feat for a tank not because it makes the tank tougher, but because it mitigates the main drawback of what you might call a 'turtle' build - one that prioritizes personal defense over everything else - ie, if the enemy can't hurt them they'll just ignore them to attack someone squishier, and the party will lose overall health resources faster rather than slower. If you're building a proper tank - like in the mmo sense of the word - sentinel is not only a good feat it's practically a must have (with a few exceptions - conquest paladins can make do without, particularly if they've taken the warcaster feat and dipped hexblade warlock for booming blade).
Anyway, I would not bother with sentinel, at least not for now. If you like Vow of Enmity and your character's lore & personality as a vengeance paladin, I'd say stick with it, and go to your DM with your issues.
A particular issue is the strength thing. 15 strength is kind of a big deal, at your level you should be rolling around in plate armor. Having 14 strength means being stuck in chain armor which is two whole points lower, and that's a lot of AC. The difference could be made up with item drops - gauntlets of ogre strength would do it, as would a +2 shield, or +2 chain armor, or +1 of both. However, asking the DM for a bunch of extra boons or magic items will probably be a hard sell considering you just picked up an amazing and extremely powerful magic sword - which, btw, congrats on that, vorpal swords are fantastic.
So items might be out. And ASIs aren't ideal, either. Like, you totally could take heavy armor master, picking up the point of strength to wear heavy armor and 3 points of damage reduction vs. non-magical weapon attacks. But that reduction doesn't scale and already isn't great at level 10, and only gets worse as damage increases and more enemies gain magical attacks of one form or another. And honestly, as a Hexadin your first ASI should be warcaster, and after that as many ASIs go to charisma as it takes to max it out. With the vorpal sword you could arguably eat the delay on to-hit and damage, but cha bonuses also apply to your spellcasting and, important given your problems, saving throws, so you'd really prefer not to.
Maybe ask your DM if you could make some sort of blood magic offering to your hexblade patron, sacrificing two points of constitution to gain two points of strength, effectively swapping your starting scores in these stats? Honestly if they let you trade two points of con for even just one point of strength I'd take them up on it. You'd definitely be paying a price, with lower stat modifiers overall, and lower health, in exchange for basically just the ability to wear plate armor, but imo that would be worth it, even given that reducing your max HP obviously isn't ideal if survivability is already an issue for you, but plenty of paladins make do on 14 constitution since the demands on their other stats are so high.
If the DM doesn't go for it though, then.... yeah, I probably would actually recommend either retraining one of your ASIs to Heavy Armor master, even at the cost of reducing your current charisma to 16, or taking it as your next ASI. Between that and retraining the combat style your AC will rise by 3 points, and if you're getting hit a lot then yeah that's worth it. At least for your character, it absolutely wouldn't be worth it for a conqueror or any other paladin multiclass that relies on offensive spells. After that, though, really, no more feats until your charisma is 20.
Now, saving throws. with +4 aura of protection, or even +3 if you retrain a +2 cha asi to heavy armor master, you should be pretty good, here? There's not a lot I can offer to help on this one, it sounds like you're maybe rolling bad. Actually, there is one thing. If you're going into a fight where you expect to be rolling a lot of saving throws, you should strongly consider sacrificing your first action to throw up Bless. Even at level 10, Bless is still a great spell, quite worthy of both your actions, spell slots, and concentration. Yeah, you'd probably prefer to be burning concentration on that fancy haste spell that oath of vengeance gives you, but if failing saves is a problem bless is a reasonable solution, and it also buffs to hit and applies to two other people, more if you up-cast it which you might have to do anyway if Shield is eating your first level slots. And the allies you do tag with it certainly won't be complaining. Sucks to give up a pair of attacks with a vorpal sword, but paladins are by design at least partially a support class, so sometimes your actions are going to go into support spells instead of smiting things. If you just wanted to hit things all day, you would have played a fighter or a barbarian.
With *at least* a +3 from aura of protection and +d4 from bless, even your bad saves should be somewhat reasonable. On average that's about what the more typical 'optimal' hexadin is bringing in with their +5 aura of protection at this level, and nobody accuses them of having bad saving throws. You'll still fail sometimes, but it shouldn't be a lot, and while it does eat your concentration, with advantage from warcaster you at least shouldn't lose the spell hardly ever.
Sadly, you won't be smiting much. Not when you want to reserve a couple 1st level slots per day for bless, and a few more for emergency castings of shield (which you should only break out if it'll make an attack miss AND you think that attack was going to do a lot of damage). That's probably going to be all your first level slots and maybe a couple of your second level slots as well, so you'll have a couple of BIG smites per day left over, but not enough to throw out a few in every encounter. It actually is probably worth your time to pick up at least one more level of warlock for that extra slot on a short rest timer. In my experience that should usually translate into two more spells per day, which goes a long way on a character with Shield and Bless. I wouldn't take it before your next paladin ASI at level 13, but maybe right after that. You could also pick up the fiendish vigour invocation which lets you start off most combats with 8 temporary hp. It's not much, but it helps.
Actually, the third level of hexblade would probably also be worth it for you, for the pact boon. The typical boon for hexblades is blade pact - but while stowing your fancy sword in a pocket dimension and summoning it whenever you need it is cool, you really don't need any of the blade pact invocations thanks to your vorpal longsword and already having extra attack. Instead, consider pact of the chain. An imp familiar would fit right in with your tiefling bloodline; is a useful little guy in general what with its grabby little hands, wings, and invisibility; and looks awesome as heck perched on your shoulder whether in imp or raven form, especially when you're in turn stacked upon your fiendish warhorse. It also would qualify you for the 'gift of the ever living ones' invocation from Xanathar's guide, which maximizes the dice of healing effects applied to you. That wouldn't make you take less damage, but at least would help you drain less resources from your party healer after the fight.
Actually, you might even go back into hexblade now and ride it all the way to the next asi. it would delay improved divine smite, which is a fair boost to your damage, but still.
If you ever do max out your charisma, consider putting whatever few ASIs you have left into inspiring leader. That's a ton of temp hp, not just for you but for your party as well. One dude with inspiring leader takes a lot of pressure of the party health reserves.
So, I guess, if we're rebuilding from the ground up, but not changing your starting stats or racial choice, I guess that's what I'd recommend.
starting stats: Strength 14, Constitution 16, Charisma 16 - not changing these just stating them for the record. Again ideally we'd like to bump strength up at least one point, even at the cost of sacrificing constitution, like if you could just straight up swap the two scores that would be better imo, but for now I'm assuming that isn't possible.
level 1: paladin 1
level 2: warlock 1 - hexblade patron, booming blade, shield, whatever else you like
level 3: paladin 2 - defense style
level 4: paladin 3 - oath of vengeance
level 5: paladin 4 - warcaster
level 6-8: paladin 5-7
level 9: paladin 8 - heavy armor master (if your DM does let you swap your strength and constitution, then take +2 charisma here instead)
level 10: paladin 9 - you should be here, with your vorpal sword picking up the slack for your primary stat which started good but is now falling a bit behind, wearing plate armor and carrying a shield, casting Bless whenever you expect incoming saving throws and Shield whenever it will stop you from taking a big hit. Your AC is 21 otherwise and your aura of protection grants a +3 to all saves for you and nearby allies. In tough fights you pop out Vow of Enmity and/or Hexblade's Curse and fish for crits - either insta-killing if you rolled a 20 or doubling a big third level smite if you critted on a 19 due to the curse. Your build maybe isn't "optimal" - but it should be perfectly functional, and you should be resiliant even in the face of the sorts of encounters 10th level parties go up against.
Future build looks maybe something like:
level 11: warlock 2 - fiendish vigour, some other invocation
level 12: warlock 3 - pact of the chain, imp familiar, retrain other invocation to gift of the ever living ones
level 13: warlock 4 - +2 charisma
level 14-15: paladin 10-11
level 16: paladin 12 - +2 charisma
Alternatively you do 3 levels of paladin first to get that tasty improved divine smite, and do the three levels of warlock after, both work fine. That puts you at level 16 with 20 charisma - a +5 bonus you apply to your attacks, damage, spells, and saves, significant improvements from your level 20 self before you even get into class features, including extra spell slots, higher spell slots, a fancy familiar, bonuses to healing both in terms of temp hp and maximized dice on healing effects, and an extra d8 damage on all your attacks from improved divine smite. Yeah there was an awkward period in the middle when your charisma was languishing a bit, but your amazing sword helped carry you through and by this point that's all in your past and you're ready to rock the final few levels of your progression hard. Hopefully you've picked up some magic armor or an enchanted shield, as you've basically tapped out the defensive boosts from class features, but even without you should be ok. And with a +5 aura of protection bless shouldn't be as necessary - though it remains a useful tool in your toolbelt and a good use of your 2nd level pact magic slots.
The last 4 levels of the build, assuming the campaign even gets that far, could be anything, really. 4 more paladin, picking up improved find steed for a fancy griffin or pegasus mount, would be pretty epic. Or 4 more hexblade levels, eventually picking up Shadows of Moil as a really great buff spell both offensively and defensively, plus some fun hexblade features like the ability to boss around the ghosts of enemies you kill. Or Maybe 4 levels of divine soul sorcerer picking up twin or quicken to use with haste. Or 4 levels of sword bard because bards are always cool. Or 4 levels of battle master fighter because action surge is a beastly ability at any level, and superiority dice give you another thing to tack on to hits, another way to profit extra from crits, and another short rest resource to ease the burden on your long rest spell slots. Regardless, at level 20 you get one final ASI, and can put it into inspiring leader, since by that point you should be champion famous across the realms. Granted you won't get much time to enjoy it, and the campaign probably won't get there anyway, but if you do it'll be a nice, party friendly hit point buffer to help you survive an epic capstone adventure.