What was so great about Ferris Bueller? Sure, you can say it was Ferris vs. Rooney but there were also a lot of moments where Ferris was just being a kid, such as faking illness to get out of school, the rivalry with his sister, his friendship with Cameron and relationship with Sloane. That all composed one movie.
Now translate that to Spider-Man. Spider-Man has Spidey (responsibilities as a hero, being a likable and quirky wise-cracker), Peter (and his infamous Parker Luck), his click of friends (Harry, MJ, etc.), the Bugle (and all of that crew), Aunt May (bills, health, worry of Peter, etc.), and the larger world known as the MCU (Avengers).
Do you see what I'm getting at here? Vulture can be a problem, absolutely, but I'm not saying he should be THE problem. THE problem should be the dual life of Peter/Spidey, and that's it. That's why I suggest Vulture not because he's not able to hold his own (unless drastically changed), but because he just adds to the overall bigger picture I envision in my head.