One thing bugs me about the trailer. Greedo blinks right when he emphasizes a word. A human would possibly widen his eyes and stare more defiantly at that right movment to emphasize the word with his eyes too. I guess a Rodian could have a problem widening his eyes more than normal, as they are so wide already, but in this shot right before the blink, his eyes get narrower so I think this could be done.

In the scene with the Death Star and the planet, I think the planet is moving too much. I think it would be better to have it stationary than to move it at all, so that we get a better feel for it being very far away, thus increasing the sense of these objects being of massive scale. Note that a moon orbiting a planet must be at an altitude several hundred times its diameter, so this would make sense.