Ok, so, fun thought/observation:
Imagine that Vega gets parked next to Bison as in Roo's personal roster. In the old SF2/4 section that would mean all the characters are next to someone they are tied to in the story:
Ryu - Ken = do I even have to talk about this?
Chun-li - Vega = Everyone remembers the fight in SF2 animated movie don't they? Vega being sent to assassinate her is a fairly common storyline in a lot of the streetfighter stuff :3
Vega - Bison = vega works (worked?) for bison
Bison - Cammy = Cammy was one of Bison's dolls
So... with that in mind who would go next to Ken? and does the same apply to Charlie and Birdie? :3