Yeah, sounds reasonable.
Back when the Project New Jersey part of the fora was still in it's infancy, I threw the idea of factions out there. The precept was to have several sides you could join, none of them good or evil, but each having their own agenda. The player would have had a predetermined goal, call it main quest if you want, and the factions would have helped the player to achieve that, he/she just needed to accept their missions, etc. The end result would have been the victory of one faction, the main goal itself wasn't important as it was there to give the player something to work towards. I thought leaving the factions relatively morally ambigious would have forced the the player to consider how far she's willing to go in order to achieve her goal. There might have been a set ending for each faction, or one single end result with Fallout-like ending movie where the game would have shown the results of the player's actions.
Eh, it's all been made already. I'm just rambling.