If I had to boil it all down, I think Kevin Drum says it perfectly. It wasn't a bad movie per se, but it was the first Star Wars movie I walked out of the theater not wanting, not NEEDING, to know what happened next.
First, the good:
1) It definitely wasn't as bad as the prequels. There were some sappy moments (we'll get to that in a moment), but overall it didn't feel like a campy movie the way I-III did.
2) It was actually kind of refreshing to see Poe get taken down a notch by cooler heads, who had their plan all along and whose only fault was deliberately choosing not to share it with the hero-fly-boy who already proved himself more reckless than anything else. In the past, he would've been the brave hero who saves the unwitting and indecisive bureaucrats ... this time he's kind of just an impulsive jerk who refuses to listen to anyone. I found that very refreshing and a satisfying take on how the world doesn't always work like an action movie.
3) They brought the 'mysticism' back to the Force. Midichlorians = blech. This movie made the Force mysterious again; it showed us things that we can't QUITE grasp, things we know have significant meaning and are trying to tell us something, and that would become immediately obvious if you just had that ONE more piece of the puzzle ... which is always just out of reach. They did a good job with that part.
Now, the bad:
4) Leia is completely irrelevant to the plot. I mean, she's clearly supposed to be a major character, but at no point in the entire movie does she actually DO anything that influences or changes the direction of the movie. The movie just kind of happens around her. She has some dialogue with Luke at the very end that I suppose gives Luke some closure, but none that changes what he was about to do anyway.
5) Snoke. What. A. Waste. Clearly something ancient, something mysterious & dark ... who just casually gets sliced in half while saying generic bad guy stuff. That's usually the point in the movie where you're thinking "that was too easy" ... except this time it really was just that easy. The ensuing fight with his guards was more exciting and more suspenseful.
6) Sappy #1 - What was with the Leia-is-Jesus-space-walk thing? She gets blown into space, then hand waves herself back in again. Is she supposed to be the Messiah? We get it, Leia is deeply in tune with the Force. But yikes, that was a dumb way to show it, and anyway she'd already demonstrated that by her connection with Kylo Ren just earlier. They could've achieved exactly the same outcome much more realistically without making us wonder if Leia is only pretending to be human.
7) Sappy #2 - Yoda. I mean WTF. After what is presumably 2 decades of absence, he just randomly appears to help Luke blow up the old Jedi temple and impart old Yoda wisdom? That scene was cringe inducing.
8) I was ok with Luke's story arc. Not thrilled, but not super disappointed either. It's plausible, although I'm still wondering how he transformed his personal failure as a Jedi Master into a failing of the Jedi as a credo. That implies Luke is a whiny baby who needs to blame someone else for his own failings ... which I suppose I can believe, but needed a little more backstory. I would've preferred a Grey Jedi direction where he really has learned that the "Jedi way", as he knew it, was creating more dischord than harmony.
9) I'm ok with how Rey's parentage was treated. If Kylo is to be believed (which, I should state for the record, I'm not 100% convinced he should be), then her parents were nobody in particular, just random traders who didn't particularly care for their little girl and needed some drinking money. Accepting that, and realizing she's more than her parentage, seems to bring Rey some closure, which I can buy. It's also somewhat backed up by her vision in the cave, where she's trying to see her parents and the cave shows her herself instead.
Rey's lesson may have shades of "be ok letting go of the past", but the lessons for Finn & Poe are "get your head out of your own ass and take a look around you". Which, as I write it, I guess kind of describes the arcs for Luke and Rey too. So maybe the lesson for everyone (Rey, Luke, Poe, Finn), is that you're all being self-indulgent whiny jerks; get your heads out of your assess, and figure out what the universe really needs you to be.