Some of my friends and I were talking about the awesome Avengers movie and we were discussing our disappointment in the death of Agent Coulson. During this conversation, I came up with a way you can save Coulson and add a new Avenger at the same time. Use his brain as the brain for Vision. I mean, this could be done and written in the story in a cool way. Even if Dr. Pym is not involved, you can have Stark invent this Vision. Since we know the movies don't exactly follow the books to a T. Anyway, just some thoughts for you to digest while your writing the sequel.
Derf, a loyal fan