Just got home from seeing it. It's 3am, and I'm still taking it in, so I'll imagine my views will change and adapt. I'm due to see it again in 12 hours, so I'll get a chance to explore it a bit more.
Overall, I loved it. It's the film Star Wars needs, going into a new trilogy. They basically condensed 4-6 into one story, showcasing the new generation of fans what makes Star Wars what it is. It just about stayed on the right side of call backs, though there were a lot. I never felt fatigued with it, and I was suprised about the things that weren't what I was expecting, and yet I loved in a different way than I thought I would.
Case in point, Kylo Ren. I thought he'd be this devote Vader groupie badass, but instead we got something far more interesting. Driver was great IMO, and I like this insight into a dark side user from a slightly different angle. Instead of viewing the dark side as the temptation, he sees the light as the thing he needs to be wary of. He's raw, and emotional, but it felt far more chaotic and well handled compared to dark side Anakin.
Ridley, whom I had doubts about, nailed it. Boyega was far more comedic than I thought he was, but I loved Finn as a character.
It felt like Star Wars, which is great. I don't mind the things they didn't explain, but I also felt like they showcased stuff that didn't need showcasing. Snoke shouldn't have been so prominent; they didn't NEED to shout about him, and he didn't need that sort of exposure. I felt the annihilation of the Republic systems was odd too; it's not as straight forward as the destruction of Alderaan, because that doesn't have a massive effect on the galaxy as a whole (apart from striking fear into all who oppose the empire). More should have been made of the impact of that attack.
It felt a bit....messy in places. No where near as simple or straightforward as ANH, but then it had a lot to accomplish. I said before I saw it, that it had to tie the OT generation, the PT generation and a new generation entirely together in a near a package to go forward into 8 and 9, and I think it did a great job at juggling all those balls. It dropped a couple at times, but on the whole it was thoroughly enjoyable. My knee jerk reaction is that I prefer it to ANH, but it probably stands behind it in terms of viewing strictly as a piece of cinema, and not an entry into a massive franchise like this (if that makes sense).
There were only two things I actively dislike; Gleeson'a accent (apart from the rally speech, that was awesome), and Poe's final run on the oscillator was a bit much.
I don't think for a second Finn will be force sensitive, and never thought that going in anyway. I was sure Rey would be a Skywalker, but I think there's enough wiggle room to allow her to be someone else, say a Kenobi. I do think though, that there's a suppression of her heritage in the character, and the awakening is very literal in her case. She's turning over bits of the puzzle throughout the film, and whilst the final scene was a bit awkward, it felt like she was committing herself to Luke as a student of something she already knows.
I also hope with Kylo, that he continues his battle with the light, and views it as an evil influence. I don't really want a redemption arc with him, because it's when he's being tormented that it's most interesting, and from a completely different angle to what we've seen before. I loved the idea they played with that he's been allowed to roam the First Order as the attack dog, but really he's just an unstable kid who has been frying ants with a magnifying class. Whilst on paper it looks like Finn (and to a certain extent Rey, though more was made of her "waking up") shouldn't hold a candle to him, you can see the emotion in the character and how rocked he is by Han's death (loved that scene by the way; was expecting it obviously, but still got nervous).
I'm kinda rambling, so I'm just going to go to sleep and see it again tomorrow. Star Wars is back!!