I'm gonna say it, this movie was way better than the Force Awakens. Yes it drags on space Monaco, and yes it's still a bit derivative of episode 5 (and interestingly of 6 too) but it also did way more original stuff than Force Awakens did, went in an interesting way with some set-ups that nobody really expected but turned out to work really well in my opinion, and also featured some great exploration of Kylo Ren, interesting development of Rey and an actual character arc for Poe. Plus it didnt hinge on nostalgia nearly as much as Force Awakens, and I liked that. There was also a lot more moral ambiguity, and a somewhat blurrier line between light side and dark side, and I really dug that. It's nice that they're experimenting with the formula, rather than just having another emperor/vader pair as the baddies.
It also needs to be said that the space battle scenes were easily the best since at least return of the jedi, and that they did a great job of establishing a tense tone that somehow doesn't feel undermined by the humour. (at least in my opinion).
If I had to make a complaint I'd say that Finn's development was a bit cliched, without spoiling anything. You can kinda tell where his arc for the movie is going to go fairly early on, and it doesn't necessarily feel like a logical starting point after the Force Awakens. I don't think they ruined the character, but it could've probably been a bit better. There's also a Leia scene, already much talked about, that felt really bizarre. That kinda briefly took me out of the movie.
I didn't mind Luke being broody. In the context of the story it makes sense to me. Whenever you question his actions it's important to remember that Luke never finished his jedi training, so it makes sense for him not to have the wisdom of the old jedi masters.