It could go several ways with me.
On one hand, I'd like to see Bullworth as part of a larger map, or a separate map you can access later in the game through a means of transportation.
I'll welcome a new setting too as long as it's not generic and fitting of a school environment.
Now, as for characters:
1. It would be cool to have at least two protagonists: One male, and one female, and you can choose their personalities (sharp and pragmatic, fighter type, etc.). I guess the best way to describe this would be to look at Indiana Jones and the Fate of Atlantis. There's a team, wits, and fist path. Team path pairs you up with Jones' love interest (Sophia, if I recall correctly) as you solve puzzles. Wits puts you up against harder puzzles, and you have no help. Fists path relies very little on puzzle solving, and more on action and fighting your way through the game.
2. They could have Gary Smith as the protagonist in the aftermath as he tries to reform his issues and redeem his name. So as he goes, he faces new problems, but also has to battle his inner conscience and issues as he goes about them. This, however, would be very difficult to pull off, given Gary Smith as a character is full of holes.
It's kind of like Kyrandia. Malcolm is the established bad guy in Kyrandia 1, but in 3, he's the good guy as he tries to clear his name and prove his innocence. However, his deranged, cynical mind persists throughout the game.