One thing that bugged me was that in Firefly: all the really bad-ass people are black. Even the preacher had many hints dropped that, while a tame teacher of wisdom then, he was a major ass-kicker in the past. This trend continues into the movie as the head bad-guy is also black. Combined with the whole 'civil war' tie-in, and I actually find myself asking is Joss is a racist or something.
But I'm sure it's just a casting coincidence that he didn't notice...