Re: Non-Cap characters/cameos you'd like to see in Captain America 2
Now that we know the movie will have Winter Soldier, I would really like to see Black Widow, and I would like to see her "betray" SHIELD in a covert mission under Nick Fury's orders. If she does, it would then be cool to see Hawkeye's reaction to that.
This could both serve the plot for CA:TWS as well as serve to help rotate the Avengers roster for TA2 if that is what MS/Whedon wants to do. (If Ant-Man and Wasp join, it might help to have Widow and Hawkeye off elsewhere to keep the roster manageable.)