Re: James Buchanan Barnes aka The Winter Solider
There definitely needs to be bucky in the movie
I can see them going the Ultimate "they were friends before" route. But I don't think it's a great idea to have Bucky be his big strong friend who looks out for him.
I think it would create some resentment in Bucky to be the big star athlete, lookin out for your little friend, and then have that friend get powers, fame, and a higher rank in the military...
(It also goes without saying that Bucky HAS to be a soldier)