I think you touched a very good point. But we have to remember that not everyone's KOTOR "saga" is the same. For some Revan was a female, others male, Revan was light or dark...not to mention that in some peoples stories, certain party members were actually killed. I mean, if/when they make a 3rd installment, I DO NOT want to see Carth leading anything because in my view, I/Revan killed him off long ago.
But, like I said, not everyone believes the same story as myself. Whomever makes the 3rd KOTOR has to take in all these variables and THAT is a monumental task...unless they make it where you have a tutorial which tells the game what happened.
I'd personally like to have another character to develop. Have Revan doing whatever, the Exile doing his/her own thing, and the 3rd P.C. doing his/her thing....but the plotlines of all three eventually converging into one cohesive storyline that makes all 3 KOTORS make sense (ala. ANH, ESB, and ROJ)
....or maybe I just have very high hopes.. "