Went and watched Rogue One today. It was fine. It is definitely the most depressing movie in the Star Wars Canon in my opinion because everybody just dies at the end, which is kind of logical because else you'd ask where they were during the events of the original trilogy. However, the movie also in the end makes you remember all the heroic exploits that follow, playing up the hope angle.
The movie also does good in actually building up the Empire as the bad guys, as really threatening and not just the "evil on the horizon". I mean yes I understand that the Empire is always the bad guys and a fascist, despotic ruler, but in Rogue One you can actually see this first hand. When in A new Hope the Death Star blows away Alderaan it is rather abstract. You are told that this is a very populous planet and you get to understand the hurt its loss causes for Leia, but you don't have first have experience. The destruction of the mining city in Rogue One is far more "personal" to the viewer because the viewer actually stepped through the streets of that city. It also showcases the callousness of the Empire since it would rather wipe out a city of presumably millions than having to defend it against the Rebels.
Similarly for Darth Vader. You understood during the Original Trilogy that he was powerful, but I don't remember where his power was really demonstrated well. Most of his combat scenes are either duels or he is leading a group of Storm Troopers. In the scene at the end you can see that he just mops the floor with a corridor full of armed guards and nobody has even the slightest glimmer of a chance against him.
I also like the change in scenery in this movie. A lot of Star Wars is set on industrial space stations, cities and desert planets (and yes, Hoth is also a desert planet). While this is also true for the mining planet, I do enjoy them showing a quasi jungle planet with a very wet climate at the beginning, as well as the tropical planet where the final fight is set.