Yeah, Revan is the obvious answer. Strange though to list the first KOTOR as a reason, I personally felt through Kreia and the few bits I have experienced in SWTOR he was fleshed out more than in his first game.
On that note, aside from Revan my pick would be Kreia. They both have what most adult Star Wars fans are looking for and contrast the surface level morals of regular star wars nicely. They are acting out of their own motivations to achieve what seems right to them, by any means necessary.
Neither Sith nor Jedi, like staring into the heart of the force.
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