Re: Who is the main villain of this movie? *SPOILERS*
Cool, glad we agree on that JackWhite.
One thing I was thinking about recently is I was really pleased how the entire trilogy avoided one of most trite (IMO) superhero movie tropes- "two otherwise unrelated villains team up because they're both mad at the hero!" (as seen in all the 92-97 Batman sequels, Spider-Man 3, ASM-2, etc.).
This trilogy incorporated a lot of villains, but it never felt too contrived. We had villains who were pawns of larger villains, villains who turned heroes into villains by seducing them to the dark side, and villains with a shared history who were on the same team all along.
Totally unrelated, but I was thinking that in retrospect it was pretty cool that Raimi's Spider-Man 2 opted for just one villain considering it was a sequel and the temptation was surely there to put in more (Black Cat was originally planned but taken out). In general I feel like multiple villains tend to hurt superhero films more than help them, but luckily this trilogy managed to avoid that by weaving plots where everything came together in a pretty organic way. Honestly, probably the most "tacked on" character was Catwoman, but she still figured heavily into the themes of the movie and I don't really consider her a villain as such.