I should have been clearer: I meant it would work in a "Wow, it's like the cartoon except on the big screen" way. Too campy for my tastes. Did you think Spider-Man 3 was overstuffed? (I loved the movie because despite that, it still moved seamlessly through the story. More content would have been pushing it)
I agree that if it was cartoony, I wouldn't like it. I don't think it has to be cartoony though. It'd have to be written VERY well, and it would have to go against pretty much all precedent set for how to write a Sinister Six story to work though. Spider-Man 3 was overstuffed not because of how much they tried to put in it, but the fact that they were sort of inept at putting it in there.
I mean, the Sinister Six would be six villains, but it wouldn't be six MAIN villains. There would be varying degrees of focus. At least two of the villains would probably not be any more developed than, say, Toad or Sabretooth in X-Men. And again, it would hardly be a "team." Trust me, I hate "supervillain team-ups." My LEAST favorite scene in Spider-Man 3 was when Venom met up with Sandman. It was so terribly written and seemed so cartoony. And I certainly don't want any "Villain Meetings," where they all sit around a table and say things like "I hate Spider-Man!" and "How can we destroy Spider-Man," or throwing darts at a picture of Spider-Man. The Sinister Six would not be organized for express purpose of destroying Spider-Man, because there's no reason for them to
hate him. It would be organized for the purpose of, say, hijacking Manhattan or something, or for some singular goal that the leader of the Six has, and their overwhelming numbers and powers would exist mostly as a precaution against Spider-Man, who the leader knows would be their primary obstacle.
It would have to be very, very well-written; probably be someone very conscious of what's wrong with a lot of comic books, but I think that the Sinister Six,
if it was well-written, would be the most appropriately spectacular conclusion to the Spider-Man series.