I've always been a big Star Wars fan since I saw the first movie in the theater when I was 6. As a fan I enjoyed the movie, but I wouldn't recommend a non-fan to run out and see this.
Being back immersed into the visual universe during the events of the original trilogy was great. I loved seeing the original Storm Troopers, the original Death Star, AT-ATs, Star Destroyers, X-Wings, Yavin-4, and all the little inclusions and nods towards A New Hope. I enjoyed the scenes with the CGI-'d Tarkin, but felt it was a little off.
The fight scene with Donnie Yen's character on Jeddah and the closing battle and space fights were fun and well done. Of course, the Vader cameos and the last epic scene were my favorite parts of the entire movie. This last scene was what we should have gotten at the end of Revenge of the Sith, instead of the epic let down of, "NOOOOOOOOOOOOOOO".
I've always wanted an adult Star Wars "war movie", and that's what this is. Of course, being Star Wars and Disney this can't be a full on R-rated gritty war drama. It tries but comes up short. Taking out the Star Wars of it, the movie feels very run of the mill and by the numbers, with nothing really surprising or special about the story or characters.
A war movie like this needs to have compelling and interesting characters that make you care about them and their involvement and motivations. Donnie Yen was good (notice I can't remember his character's name), but none of the other characters were memorable and the acting was very average.
Jyn's character is nice to have a female lead to balance out the all-male group of Rogue One, but I never really cared about her as much as I loved Rey in last year's The Force Awakens. Her and Cassian never really came off as having good chemistry and he was just another forgettable character to me.
K-2SO was good, but I wondered if he was just included to add a little bit of Star Wars fun to the movie. I would have liked to seen it, before all the reshoots and wondering what was added or removed. Was this a darker and grittier war movie, or was K-2SO added to bring some fun & levity, or was it just not up to par to what we got... I had EXTREMELY high expectations for Rogue One, but I'm really feeling disappointed.
I want to see it again, but honestly I just want to fast forward through the story and watch several scenes again. This may change, but right now I'd rank them:
1) The Empire Strikes Back
2) A New Hope
3) The Force Awakens
4/5) Revenge of the Sith/Return of the Jedi
6) Rogue One
7) Attack of the Clones
8) The Phantom Menance