My more concise early take of the film:
It’s fan service done right, and relegated to its own movie. The same types of things I didn’t like about TFA (nostalgic rehashing of the OT) found their proper context in Rogue One. It’s not an important film like TFA is, and perhaps that is a good portion of the reason I enjoyed my first viewing of it more than TFA. By its nature, TFA will receive more views in the long run and served a purpose. But Rogue One is a thrill ride for the already established Star Wars nut.
I would not include Rogue One in a ranking of the Star Wars films, but would rank the anthology movies separately. This was like going to see a WWII period movie, not the next chapter of an ongoing mythological story.