I wish Bucky had the chance to kill Rumlow in ca:cw. Not only would it be cool to see them fight (especially if Bucky’s knife was involved) but it would’ve been a heroic moment for him as well. Rumlow decided to continue terrorizing innocent people, even after Hydra fell with Shield. This moment would prove to the audience (and the avengers) that Bucky is indeed against evil and actually wants to protect people from harm. In ca:tws, Rumlow only saw Bucky as the stoic, brainwashed “asset” who can be used and abused without resisting. Imagine how shocked he would be to see the damage Bucky can inflict when he isn’t being controlled by anyone but himself.