Re: What villain should be pulling Winter Soldier's strings?
Here is an idea.
The Soviets find him and make him into the Winter Soldier, using him from the fifties to the eighties. Late in the Cold War, with the USSR beginning to come apart, an East German spy called Heinrich Zemo gains control of the Winter Soldier, and after the fall of the Berlin wall, goes to business for himself, using the Winter Soldier as his personal assassin to gain wealth and power. Later on, his son, Helmut, takes over.