I was really looking forward to the NYY/STL combo since those two teams have the most World Series wins, but surprisingly, there aren't alot of marquie players that played for both of those teams. The best players from that combo include Dazzy Vance, John McGraw and Lance Berkman... I'm probably using none of those guys.
So, you never know which combinations will produce the studs.
That being said, I do have some nice exclusive players to choose from (Gehrig, Mantle, Joe D. from NYY and Musial, Gibson from StL, M.Schmidt from Philly).