Underwhelmed.
The first hour or so, let's be honest, is pretty rough. Bad writing, uninspired acting.
I was desperate for them to spend more time developing Jyn Erso's character — something more about her inner life, or even her outer life, beyond the fact that she has been a resentful wanderer. Even a few more close-up reaction shots would have helped — if it's not on the page, let Felicity Jones act some meaning into it. They made a decision to define Jyn Erso entirely based on her relationship with her father, and that turned out to be a serious mistake.
I think the movie failed to create any new iconic images of its own. I can still remember a whole bunch from The Force Awakens. Rogue One feels masterfully-constructed in many ways (visually), but it doesn't have many singular wow moments.
I found the music oddly annoying at times. They tease you with parts of Star Wars themes, then diverge and fail to create anything particularly fresh. Even The Phantom Menace gave us a new memorable theme.
SPOILERS
Things I liked: Pretty much everything from the moment they brand themselves "Rogue One." It was all exciting and mostly great.
The moment when Jyn *might* have used the force to let them land, by clutching her kyber crystal necklace.
I like the idea of a pseudo-Jedi. That was a good character.
I was genuinely inspired by these characters' courage and the sacrifices they willingly made. I suppose that's the main thing the movie needed to accomplish, and it did so with real emotional weight.