After thinking about a bit, (not much is the truth)
I think
we should start the game with the exile, who is now travelling to outer rim and his connection to the Force has also been reduced (this could also give the opportunity to have him as a non force sensitive character) and then later, something about lvl 15 you meet Revan who has been caught by the true Sith.
The exile then comes with a plan to save Revan (as Revan is the only one who can fight the true Sith) and in that the exile may die or not (the player should be able to choose, maybe in regard of LS or DS).
Then you have Revan, who is also terribly weakened after his cappture. You then go back to known space and gather your stregth by seeking out ohter Jedi (Master Vandar could be one of them or you simply revisit Koriban or Atris academy to study some Sith holocrons).
During that time you meet up with new and old NPCs.
But something like this would require the game to be truly epic, maybe 50-60 hours or more.