I really have a hard time believing that the whole Vulture/Vultress thing was a genuine plan for Spider Man 4. It seems like Raimi had already grown tired of dealing with the studio. He must have realized how the 3rd movie had fallen short and I can't imagine him truly wanting to go forward with a 4th movie in that same situation.
He didn't have enough vision or drive or whatever u want to call it to push thru his true idea of Spider-Man 3. I really believe that, in creative projects, bad things are born from lack of momentum. If he had really been into the third film and had an idea that he was on fire about, I don't think the studio would have been able to wedge Venom in. They would have backed off or been shot down because something else real would have been happening.
So it's hard to imagine anything realistic for Raimi's Spider-Man 4 because I don't think it could've happened. Outside of something outlandishly horrible just to fulfil obligations.
But it is interesting to imagine what Lizard might have been for a Spider-Man 3. I think that Raimi would've turned in a much better and more horrific version of the character. In lab coat and campier, but more like a true horror movie beast. Webb's version actually captured the physical threat and bestial menace of the Lizard pretty well, i thought. but Raimi would've been able to better get across what Connor lost in the transformation. He would've included his wife and kid and the exaggeration, the theatrics or 'camp', would've served the character better I think than Webb's more levelheaded take on him.
But you would think the same about the Green Goblin, or Venom. But, I agree with the poster above me that Webb will do a better job on both of those characters if given the chance.
I think Raimi just didn't like Venom and it came down to that. If he had latched onto the character somehow and didn't feel like he was being railroaded into something he was already working on, I think Raimi would've ruled on his version of Venom.
Why his Green Goblin didn't work, I don't know.
I would've loved to have seen a Kingpin/Enforcers/Hammerhead kind of mob movie as Raimi's first. Shocker or Electro working as muscle for some mob boss would've been perfect Raimi. Doc Ock was perfect Raimi and Mysterio would've been perfect Raimi. Scorpion would've been pretty cool too.
I'd love to see Webb do Green Goblin, Venom or a version of the clone saga. I really hope Webb's got ideas for bringing in some clone stuff. I know how awful that could possibly be, but I think if he went the Ultimate version, it'd really suit him.
Somebody besides either of them should do Kraven or Morbius.