The villain of Captain America: The Winter Soldier, Bucky is going to be making a complete U-turn in this film and working for the side of good, presumably after getting all of his memories back. His arc is an extremely interesting one, and hopefully it won't get shoved to the background too much here with everything else that's going on. His redemption arc could actually point to the fact that he's going to die, as it'd make it much more poignant than if he were still a villain, but I've got him quite far down because it'd be a total waste of the character's potential. Sebastian Stan was excellent in The Winter Solider, and will hopefully continue that in Civil War. He could be an increasingly big part of the MCU going forwards, especially in the really long-term post-Infinity War, and is the most likely to pick up the shield when Chris Evans does exit the Marvel world.