He's such a cool, under-used villain with a lot of unused potential. And with it revealed that he didn't kill Bucky (Which was the whole reason Cap fought him with such hatred) and since everyone else returns (And with his son, who I feel is less threatening villain, gone), I feel it's time he made a return. He could return to re-form the Masters of Evil, and menace the new Captain America (Bucky himself). I see him as a great enemy for Bucky, because if not for Zemo, he never would have become Winter Soldier. I could also see Zemo somehow trying to bring back Cap so he could kill him himself since he'd probably feel cheated out of his victory. ANyone else want to see him return?