I agree that the beginning was strange in that it had the CSI type [Planet Name/ What it is famous for] on like 4 planets within the first 10 min, and a few we never even see again. The one big problem with prequels like this that I have is that, you already know the outcome, so there isn't much tension. If there was no episode IV and all this was happening it leaves you to think "what happens if the fail" or "will they fail" but since you know they get the plans anyway there is no tension. But with how they told it, the story was very well done. Though I liked Film Theory's video on correlating the new Rogue One characters to the knights of Ren from some star wars book that was released after episode VII (you should watch the theory, its pretty cool) the way the heroes went out was pretty good, but most of them happened pretty rapidly, so there was no emotional impact after the first couple because it seemed like "oh this is the part where they all start dying" and it lessens the effect. I did enjoy K-2SO, he was pretty funny, sad but valiant the way he went
I liked the inclusion of Tarkin, even though from playing too many video games (and from a minor spoiler) I could tell that he was CG just by looking at him. Its very impressive how real he looks, but its always something about lighting and mouth movements that give it away to me.
The fleetfight was pretty great, something episode VII lacked completely which I was sad about, but it was pretty awesome here, and the design of that mon calamari piloted capital ship was pretty cool looking (if not pretty stupidly designed
The part that ties the end of Rogue One into Episode IV was pretty great in the way it was done (that Vader Rampage tho
) and how it looks like you could put in a DVD of Episode IV and immediately pick up where Rogue left off without any time gap.
All in all, it was very enjoyable movie, much better than Episode VII to me. I just hope episode 8 builds on the way Rogue was written/directed/shot instead of how 7 was.
*also to whoever was asking (Bfett?) it did show a shuttle going to the disabled Rebel Capital ship, in which it is assumed Vader was on, and he was murdering all the rebels outside the airlock between the Capital ship and the Corillian Corvette.