Hello there!

I'm currently preparing a long-term campaign that I expect to start spring/summer next year. I'm having oodles of fun writing it, along with the characters, biomes, etc... BUT I'm conflicted about the number of "side stories" that are currently in it.

I.E. The campaign starts off on an airship that functions as a floating military base (so it has shops, amenities, etc). Originally, I wanted to give every "interactable NPC" a side quest, so that no matter where they decided to go, there would be something fun planned, but then have that be the ONLY one they did until the next core story beat.

So if there were 10 NPCs and they interacted with one, it would have its own unique quest line, and then the rest of the NPCs would just function as regular people, shopkeepers, etc with no other quests.

The more I dived into this and started creating the side quests, I fell in love with the stories and characters and wanted to add them more and more. I have reservations about having the players do 8-10 "side quests" before hitting the next big story beat though. (For context, I expect each side quest to take roughly 30 to 45 minutes each. Only a couple entail combat.)

What are your opinions?

So, "side quests" as such are good. They give texture to the world, making it clear that not everything is about the Big Events.

However, you seem to be structuring things very rigidly, like this was a video game.

D&D can be a lot more free-form than that. It depends on the players, of course, but you have to be prepared for them to go haring off on their own, completely ignoring all the "plot here" signs. Or deciding one particular NPC is their bestest buddy, or that an NPCs "side quest" is actually Plot Important.

So, you have NPCs, and they want things. You also, from the sound of it, have a Single Big Plot going on.

Instead of a framework of side quests and plot beats, I suggest using the two to manage the pacing. Use the NPCs, actively, to spread the Big Plot out. If the PCs are faffing around with nothing to do, somebody comes to them for aid or whatever. It doesn't need to be one side plot per NPC, either. The stuff the players engage with should become more important. The stuff they're not that into should resolve itself through other means in the background, possibly with consequences.

Meanwhile, the Big Plot is cooking along. If they spend too much time with the NPCs, it impinges on them directly. If they actively ignore it, the situation gets worse, and now it's going to be harder for them to fix it.

Also, just as a side note, just because you like your NPCs, don't insist that your players do. Be prepared for them not to be that interested in these people and their problems, because they have a Big Plot to resolve. You may need to find other ways to manage the pacing.

Preparing side quests is the "practice" of GMing I think. The "practice" being the stuff that you work on that will probably never be seen.

It's the hundreds of drawings of a hand before you get the fingers just right. It's the thousands of laps in the pool before you win the swim meet.

So, these side quests you're preparing, they're super important to your game for worldbuilding, and super important to your process as a GM. But your players may never interact with a certain NPC, or it may just never be the right time to take on that task. And that's okay. It's still part of your world whether it's uncovered or not. 

It's okay to work on stuff and keep it in your back pocket until just the right moment- and you pull something out fully prepared that your players weren't expecting. It'll blow their minds

As always with DMing, the thing to remember is your players may not do it. This can be very obvious in world building, if they just decide not to go to some country or place you’ve developed. 
But it’s also true with side quests. By their nature, they’re both missable and skippable. If the PCs never talk to that specific NPC, they’ll never know there was a side quest there. Or they hear the story and for either player or character reasons, just decide not to do it. 

So my advice would be, have some ideas for them, but don’t really start working on developing them too much until the party actually starts doing them. 

Thank you! 

This is a lot of good information, I appreciate it very much. 

I agree that I'm probably structuring this out too rigidly. I think that stems from the games where I was a player, and the DM didn't seem to have any idea what to do, so I think I might have overcompensated trying to plan for *everything*.

It's a great point that I could spread the "main plot" into the NPCs and side content to indulge my players with what they are enjoying most, I think I'll see how well I can do that!

And as loathe as I am to admit, I'm sure if I were on the player side, you're right, they may not like or care about these storylines at all haha. Something to keep in mind before I go too hard in on any of them.

Yes! I was thinking of this the whole time too! 

Something like, "Man, I bet people that worked on games like The Witcher, only to have people not do their favorite side quest feel very similar."

I'm mentally preparing myself to let 80% of this additional content go undiscovered, or sit in a vault somewhere that I hopefully get to pull out sometime haha!!

There is a good side to overpreparing, which you hit on here, and that's the adage that no prep is wasted. You build a dungeon and the players don't go there? Well, next time you need a dungeon, its already done, with some updates to the enemies. Or save it for a different campaign.

One good piece of advice I landed on accidentally is to have the shell of a side-quest available, and to make the door slow to open.

In this case, that means I had a tower for the party to investigate, if they wanted to. I decided roughly what it was (a wizard made it to house his treasures and then never came back) and put a decent fight at the entrance. The party decided to investigate, then they had the big fight, a little roleplay (do we want to go here, is it important enough to stop our main quest, etc) then went in. The doors slammed shut and the tower sealed them in, and because of that big fight taking up loads of time, the session ended.

As a result, I was able to prep the rest of the interior of the tower, now knowing that they were going to go through it. Until they commited, the tower was empty, with nothing but the concept of a plan(tm) inside of it. By the next session, it was full of traps, peril, doom, monsters, doom, riddles, and peril. Oh, and traps.

So conder the following slow-entrances to the side quests to spare you all the prep for a walk-past:

1. The quest-giver is a long distance from the quest-zone, meaning at least a session of travel between "why yes, we will recover your walking stick!" and "Ah, here's the cave with the walking stick in it!". This gives you time to prep once they have accepted.
2. The quest opens with a tough fight which will slow them down. Prep about 1 sessions worth of fights at the entrance. Make them tricky to slow them down more (enemies which phase in and out, flying/climbing/burrowing enemies, enemies which strike from the shadows then disappear, etc.). Then perp between sessions for what is behind those fights.
3. The quest giver will say "meet me at the inn of the prancing pony on September 22nd". The party will have to wait a little before they start the quest, and you will have time to prep it.
4. Something else related to another plot happens. They are ambushed by cultists of the cult they have been fighting for weeks as they approach the cave of gnolls, for example. You could even have the Gnolls emerge and start fighting both sides, allowing a bigger, more dramatic fight as the Cultists become surprised allies for the short window it takes for the two sides to reduce each other to manageable levels for the party to prevail against.