I had an interesting idea for a Sins mod but don't know if it is feasible or not. This would mainly apply to single player, I think. Let me know what you guys think.

What if, when a game was over, and you were declared victorious, you could continue the game as a rebel group within your own empire. You could start with something as simple as a small cultural drain and build up a small pool of resources. Then, when your "rebellion" culture reached critical mass, you could take over your first planet and hastily set up defenses for the unavoidable attack from the fleet you just previously used to control the galaxy. You could then proceed to attempt to best the AI while being surrounded on all sides by the enemy.

I think this would give a really interesteing AI challenge and could make a game last forever with rebellions springing up over and over as you continually bring new order to the galaxy.

I guess it would even be possible to bring this into multiplayer, where players could join and try to initiate a rebellion within a current game.

I haven't played this game very long and haven't explored many of the balances. What do you think?