I actually kind of like the idea of an Imperial Civil War, if for no other reason than an excuse to get chrome stormtroopers! But that sort of scenario to me would have made a lot more sense 2-3 years out from Jedi maybe, not 30.
Really, I guess I just feel like it detracts from the "ultimate happy ending" fantasy in my head where the people all rose up right after ROTJ and the Imperial machinery was dismantled overnight. The Republic was restored and their was a golden age of peace and prosperity free of Sith, Imperials, and Vong.

Childishly naive maybe, but I was seeing the movie as a kid after all.
I also feel like it's kind of a been there done that type of thing where I was hoping for something less derivative of the first movies. But that's not to say they can't make it all work marvelously. They've hit all the right notes to this point anyway.