Good choices. I love the idea of Javier Bardem in almost any role in part 4.(even if he is Spanish not Italian)
I also like Joaquin Phoenix and I think Al Pacino would have to play the Don. Michelle Williams is a fabulous actress (My week with Marilyn, Blue Valentine) She would be a great addition. She doesn't look very Italian but neither did Diane Keaton! Oh also how about Casey Affleck? He is really good at playing bad guys ("The assassination of Jesse James", "The killer inside me"-super creepy movie by the way)
