I don't think that ruins it Buff. Makes complete sense that Luke would become one with the Force just like all other perished Jedi. And it would be cool to see him take an Obi-Wan role of guidance, but I wouldn't want it to the point where ghost Luke was running around actually doing things.
I like the ambiguity behind Leia too. All things considered, that would be a movie worth watching for sure.
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