That's an interesting idea, but it would be virtually impossible to script for all of the possibilities from the first two games while including both the Exile and Revan as playable characters in the third game. You would almost certainly have to make some assumptions about the way the previous games were played to make that happen.
That said, I would ultimately rather see the devs incorporate a canon ending into a K3 game instead of trying to handle completely open ended stories from both games. I know that leaving both characters ambiguous avoids offending anyone, but the story could turn into an unintelligible mess as a result. But, who knows, maybe they'll come up with something more clever than I think.