A rebellion as a way to get out of Fort Joy would be pretty neat, though all of the characters fighting at once would be really hectic. You'd probably only be able to recruit some of the prisoners, like Griff's gang and the arena fighters and a couple others. It would take a lot to convince everyone to join in, but it could be a really satisfying solution. Probably would entail some magister buffs, given you can already basically take them by yourself (at least, with some good builds).