Re: Who would you let Joss Whedon kill in Avengers 2?
Pepper Potts if she's not already dead by Iron Man 2. That will create good reason for Stark's alcoholism to spiral out of control. Then if RBJ is finished with the role by Avengers 3 he can sacrifice himself or what not instead of putting the character through countless recasts, etc.
Maria Hill was introduced too soon to get killed off, same with Hawkeye. Nick Fury could possibly go but I don't see it.