The MCU may have Spider-Man, but Sony has Spider-Men. Oh yeah, and Venom, but we're not going to talk about that. Into the Spider-Verse is regarded as the best Spidey film to date, so you can only imagine how much work will have to be put into its sequel.
Slated for October 7th, 2022, there's so many possibilities this one could exercise. However, here's three that they should prioritize.
Develop The Relationship Between Gwen And Miles
This one was already a given, since that's what they're reportedly going to do. It was smart for only focusing on their friendship in the first one, and letting a potential romance bud later on. In the comics, they had a little thing going on. And by little, I mean they've gotten married and had two kids in an alternate universe.
So take it slow, but make it show. Peter Parker's Spider-Man has always had girl drama, so Miles probably won't be any different.
All New Spider-Men
The other Spider-Men we saw in Spider-Verse was just the tip of the iceberg. The comics possess hundreds of different Spider-Men from different dimensions. Bringing the ones we already saw back would be a boring move. Bringing in new ones could create plenty of new dynamics. For instance, imagine introducing Spider-Punk. He's a Spider-Man who's a guitarist rock star from Earth-138. Spider-Gwen is into rock and roll herself, since she's a drummer. That could present itself a problem for Miles, as he'd be jealous and it could make a love triangle of some sorts.
Spider-Man 2099 is an obvious choice for the sequel, considering he was teased in the post credits scene. And if you want a silly one, there's Spider-Ma'am (Aunt May), Web-Slinger (a cowboy), and Peter Parkedcar (I'm not making that up. There's really a dune buggy version of Spider-Man).
Bottom line, there's a whole boatload of options here. So the sequel should really use it to its advantage.
The Easter Egg We've All Been Waiting For
Yes, I'm talking about the Spider-Trinity. Somehow, someway, the sequel should have a reference to Tobey Maguire, Andrew Garfield, and Tom Holland. Whether that's getting all three of them to voice their web-slinging heroes, or just use their pictures as a throwaway joke. It's something fans wanted to see happen in the first one, but the first one was ambitious enough as it was.
Now with a sequel and a prominent following from the fans, they can pull off something like this. It's not a story driven requirement or anything, but for pure fan-service... It's a must.
Overall, the Spider-Verse has quite the road ahead of them. Topping its predecessor will be practically impossible, but the sequel should be a big hit nonetheless. It will be some time before we even get a trailer for Spider-Verse 2, but hopefully it's worth the wait for Miles and his Spider-Army.