I dunno, Steve won't initiate a physical fight, but he has no problem provoking one if the other guy deserves it. XD; See: the dude in the theatre pre-serum in the first movie. But yes, he's more likely to do the sharp words and Strong Disapproval than Bucky is.
Bucky is doing a lot better mentally than he had before, and he doesn't give himself enough credit sometimes.
Oh man, the possibility of a pet you're watching getting sick while you have them has got to be a big source of worry. @_@