It's a bit uneven, but good. Very self contained, good characters but not the best chemistry within the group. The Droid steals the show.
The side characters are arguably better than the leads, they are pretty dry and don't have enough time to make their changes stick.
Visually great, but also uneven - I'm not yet sure how to put it, but I feel like you can easily spot the reshoots. The lighting, the sets, the camera all look off in those scenes.
In the beginning when the guy with the broken arm first spills the info about the Death Star, it looks like a cheap, small set filmed with a whole other camera and added greenscreen while the rest of the movie has a very cohesive feel to it.
Same thing with Vaders first appearance. It stands out there even more, because Vaders tank and the end of the scene look different from the stroll and the conversation... Pretty weird.
The movie as a whole doesn't really feel like it was tempered with from executives too much. It's way darker than any Star Wars movie before and it truly feels very different from the other movies. When it comes to blockbusters, it feels a bit like Mad Max. It's a project headed by a man with a vision that he tries to recreate. While it worked out perfectly in Mad Max, there are bits and pieces here that are way less elegant. But overall it's very far removed from the formulaic Marvel Blockbuster or stuff like Episode VII. The fact that this movie is a real prequel to IV without any obvious ankers to continue with any of the characters - great! More of that!
When VII is one end of the Star Wars spectrum, this is on the other end.
Loved what it dared to be, even if it's not as good as it could have been.