First time playing a Bard and trying to plan out my spell list. I tend to be drawn to spells that require concentration or have Wisdom saving throws. I feel like my list needs more versatility so I can be effective in encounters. Any advice on spells (and associate tactics) for considertion, or better yet, any spells to avoid? I am currently at 8th level. 

Also for Magical Secrets feature, is worth taking a cantrip as one of the "two spells learned form any class", or should this just be reserved for high level spells and stick with Bard cantrips? 

Thank you for any advice. 

Well - you can get incredible mileage from Stinking Cloud. But it's at the risk of becoming Mr. Stinking-Cloud Guy. As in, it's so good it may become your primary contribution to combat.

Are you looking for battlefield control, ally buffs, enemy debuffs, out of combat spells, or damage? That'll heavily influence the decision. Off hand I'll mention Silvery Barbs as a great 1st- level spell to keep handy. 

My advice is make sure that slightly over half of your spells don’t require concentration. You will want to be able to cast spells while you’re concentrating on your big control spell. 

Let's start with combat and battlefield control spells.

I like "Bane"  as a debuff and use it as often as I can, but it requires concentration. Trying to figure out a good follow spell(s) to build off that but I keep being attracted toward spells that require concentration. My current go to spell for damage is "Shatter". 

Thank you.  Question on the spell; it says targets use their actions retching and reeling, but they can still move out the cloud, correct? So is the effectiveness limited to roughly a single round? Or am I missing out on some additional tactical advantage. 

OK, I love Bards, but I really love Lore Bards.  Are you a Lore Bard also with a 6th level Magical Secrets?  It makes a big difference which college you choose and it may also have quite to do with your party and how they like to play.

So, my first Cantrips are Prestidigitation and Vicious Mockery.  Prestidigitation is extremely versatile out of combat and can be used in some specific situations in combat such as setting a candle in a pool of oil and then lighting it at the right moment with Prestidigitation, but I digress.  Vicious Mockery isn't great but I take it because of thematic consistency.  There are plenty of good cantrips to choose from that you may find better than these, but I like them.  My third cantrip is usually Mending.

My first level spells are usually Bane, Charm Person, Dissonant Whispers and Healing Word.  Bane allows me to do some battlefield control.  If we're set upon by ten orcs and I can handicap three or four of them with Bane, then my party can focus on the other orcs first knowing these orcs under my spell will land many fewer hits.  Charm Person is mostly OOC and thematic.  That's why I take it.  I don't think it is an AWESOME spell, but it is good and I take it anyway.  Dissonant Whispers is a good combat spell.  It gives your frontliners a chance to use their reaction, delivers decent damage and takes an enemy out of the battle for a full extra turn because on their next turn they have to retreat from you.  Healing Word is a Bonus Action spell so you may cast it to bring someone back up and still use your action for Vicious Mockery or a rapier poke or something that isn't a spell.

My Second Level Spells are not thrilling, but that is because the PHB spell list isn't thrilling.  I usually take some combination of Invisibility, Silence, Phantasmal Force, Heat Metal and Hold Person.  Obviously I take three of these or fewer, and it depends on how my party plays.

My Third Level Spells are Dispel Magic and one of these; Leomund's Tiny Hut, Stinking Cloud or Sending.  Dispel Magic is necessary to rid one of your teammates of some sort of curse.  The others are also party dependent for me.

My Lore Bard's Sixth Level Ability ... gives me two more spells up to 3rd level, so I take Counterspell and something else.  I look hard at Fireball because ... well ... it's Fireball.  But I may take something like Thunderstep, which allows me to save a teammate from likely death and deliver damage.

My Fourth Level Spells have to include Polymorph and Dimension Door.

Also with a Lore Bard you get Cutting Words, which isn't a spell, and it's a Reaction.  It is one of my favorite abilities in the game.  And you get all the other awesome abilities as a Bard too like Font of Wisdom, Song of Rest, great RP with Charisma, and ... and ...

As for an extra cantrip, I'd consider magic Initiate or something to get another cantrip before I used one of my Magic Secrets slots.  But you do you.  

Finally, if you can, talk to your DM about getting an Elven Chain Shirt, which a medium armor that you may wear as if you were proficient with medium armors.  It's pretty awesome to get that boost.

Good luck and have a great time Barding, wherever you are.

I really like Dissonant Whispers - provoking opportunity attacks is super nice - and it's a WIS save

Faerie Fire, Hideous Laughter, Heroism are good 1st level.  

Blindness/Deafness, Lesser Restoration, Suggestion 2nd level.

Bestow Curse, Dispel Magic, Fear, Hypnotic Pattern 3rd level 

Confusion, Dimension Door, Greater Invisibility, Polymorph 4th 

These are decent picks in my opinion as well as some of the ones mentioned above  

I would NOT take a Magical Secret cantrip, none are that much better than Vicious Mockery (disadvantage is nice)  to be worth a secret.

Counterspell is an incredible spell and well worth a Magical Secret.

In addition, strongly consider some of the Paladin only spells.  They tend to be slightly better than other spells of the same level in part because a Paladin is going to get them at higher levels. In particular, Find Greater Steed, Banishing Smite and Circle of Power are very good.