Awesome, awesome post.
Love it when the Hero and Villian mirror each other in some sort of way. It allows the thematic message of the story to shine through.
The Raimi Venom was not intrinsically bad, just rushed. You give that character extra time to flow, and it would have been fine. That's a testament to Raimi's skill that he can create a fair bit of depth for a character he wasn't really interested in.
Let's look at the other villians;
Harry's story was built up over 3 movies
Sandman's was heartwarming, about forgiveness and tied in thematically with Venom, they both had some out there relationship to Uncle Ben.
It all comes together, it all ties together. It's those words, "Great Power Comes Great Responsibility". They resonate through the series, its about Uncle Ben, it always was, and its about Peter encapsulating those words, Spider-Man is just his way of doing that. I'm kinda sad that a dance scene makes some people forget that.
SM3 was a good movie, it was just rushed and altered too much.