I'd like to see them do what Saints Row did, where you can completely make your own character, male or female, and from there the story would revolve around them. It could have been exactly how GTA V was, but for instance, if you chose your character's personality as crazy, you would control Trevor's story line, but with the same supporting characters, or if you chose laid back/ambitious, you'd be Franklin.
There's just something really great about playing with a character you fully designed. That's why I love sports games.