Luke. It’s his arc (in true Star Wars) and although Vader is iconic and important, Luke pips him with being the genuine hero of the story who you see grow into perhaps the best version of a Jedi.
Side note, the scene with Vader and Luke on Endor is my fave scene in the entire trilogy, it’s where Luke wins just by talking and leaving his back turned to his father. I don’t know if it’s meant this way but it’s how I like to imagine it, you see Vader almost struggle as Luke really does turn the screw regarding the good in him, it’s almost as if he has to steady himself ….. and this is VADER we are talking about. Anyway, that’s what I take away from that scene.
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