I'm in favor of Lizard. They've already established the Curt Connors character with Dylan Baker in two films, why not bring him back? And I like the idea of Kraven, if you have to have two villains in the film. Me, personally, I'm happy with one bad guy per film. Spider-Man 3 was a wreck for most of the film, partly because there were too many plot lines.
Venom should have been the solo villain in a movie, not tacked on. If they hadn't used him in 3 then 4 should have been his film. Sandman could have stood on his own in 3 and that would have been fine.
They could also skip Black Cat IMO. If Dunst doesn't come back as MJ then I'd be all in favor of introducing Felicia Hardy, otherwise, skip her. Save her for another film, if they do another. Don't throw **** in just because this might be the last film...which is basically what they did with Venom.