TOO MANY VILLAINS
Okay. Raimi's trilogy failed because SM3 sucked. SM3 sucked because too many villains. What does the next series do? Use too many villains. Of course, SM1 didn't do this, because back then at least they wanted to make their own story instead of trying to compete with the MCU by forcing the Sinister Six down our throats.
What's the new film already doing? CRAMMING THE SINISTER SIX DOWN OUR THROATS. JUST STOP. We don't NEED a Sinister Six movie. Just CANCEL IT. Focus on Spider-Man. Look at the roster, we got guys like Kraven, REALLY GOOD CHARACTERS, but they're just going to be one-dimensional henchmen now thanks to the Sinister Six being crammed in. Introduce all of the Six one-by-one in different movies, then make a Sin 6 movie, not introduce them all at once and ruin each character's development and personality.
Kraven, Vulture, Mysterio... we've never seen these guys on film. How about give each of them their own movies for them to be the villains of, then cross them over? That's how Avengers worked. DC is doing the exact same thing with Justice League, by putting Aquaman, Cyborg, and Wonder Woman in a movie called Batman Vs. Superman. Not Batman Vs. Superman Vs. Aquaman Vs. Wonder Woman Vs. The Flash Vs. Etcetera.
Same thing with this. At least DC is going to do separate films focusing on all their characters, but the Sinister Six characters are probably not going to be seen apart in individual Spider-Man films after this.
TRYING TOO HARD TO FIT IN WITH THE MCU
Spidey Versus Iron Man! Spidey Tries To Join Avengers!
Hm...
NO.
You might be like "OH BUT HE NEEDS TO JOIN THEM BLAH BLAH BLAH", but NO! Maybe not until Spider-Man has been around in the MCU long enough to even be able to fight half the guys the Avengers fight! It's been said that he will be a rookie hero, still in his high school years... plus, Spider-Man was always supposed to be an outsider! On his own!
I mean, Hulk was also supposed to be an outsider, but clearly Joss Whedon has some deep, burning hatred for the Hulk, so...
ANYWAYS. This is why I absolutely HATE Ultimate Spider-Man. He's an outsider. He's not on a TEAM... he's not a SHIELD agent... maybe the occasional team-up, but for CRYING OUT LOUD! NOT EVERYTHING HAS TO BE ABOUT SHIELD OR ASSEMBLING THE AVENGERS! Why can't we expand the MCU beyond just setting up the Avengers movies? Why can't we just have Spider-Man in his own little corner of the universe? Of course, he'll be in Infinity War, but can't that just be because the whole thing's going on in New York, and Spidey happens to live in New York (just like everyone else in the Marvel universe)? Not because SHIELD recruits him, or because he feels a need to join the Avengers... Spidey shouldn't be all about taking down HYDRA or fighting aliens. Not yet, at least. He should be more about fighting the little, close-to-home threats that SHIELD and the Avengers don't have TIME for!
Just have Tony Stark make a cameo. Or name-drop Stark Industries as the biggest competitor of Oscorp. Something like that. Address the whole Chitauri invasion, the Ultron thing, but don't have SHIELD trying to recruit Spider-Man, and especially don't turn this franchise into a "Marvel Team-Up" thing...
Spin-Offs
I already addressed Sinister Six up above, but with this Venom movie (I'm not sure if it's still happening but it most likely is), I'm concerned... please don't rush in the symbiote already! And please don't just introduce the symbiote in Venom and completely skip Spidey's time wearing the suit! Just do it RIGHT for once!