I left the theater feeling a general unease, an unfocused anger that took me a while to understand. Now that I've slept on it, I think I have a handle on the source of my ire.
The new movies have deconstructed and destroyed the heroes of the original trilogy.
The OT heroes were Luke, Leia and Han. Luke was defined by being a jedi, and his purpose was to "pass on what [he had] learned." He failed, then gave up, then cut himself off from the force and went into hiding. Leia was defined by her belief in the Republic and her struggle to restore it. Despite the Republic prevailing over the remains of the Empire, Leia was forced out of the Republic Senate and driven into a sort of exile while the Republic disregarded the threat of the New Order to its peril. In The Force Awakens, the Republic is effectively destroyed when the Senate and the Republic fleet are blown up, and in The Last Jedi her failure becomes complete as the resistance is decimated and her allies abandon her. Han Solo was not an idealistic crusader, what mattered to him were the people in his life. Han didn't care much about the Jedi, but he cared about Luke. He didn't burn with Republic patriotism, but he loved Leia. What do they do to Han? His marriage is ruined, his only child estranged, and even his fellow scumbags seem to have all turned against him. Only Chewy and Maz seem to want to have anything to do with him, and when he tries to reach out and mend his relationships his failure becomes tragically complete, as he is contemptuously cut down by his own son.
The message is clear: the "heroes" of the Rebel Alliance are abject and complete failures, and it is up to Mary Sue and the fresh-faced millennials to clean up the mess they've made of things.
I grew up with Star Wars. I saw the original Star Wars (later "A New Hope") in 1977, at the age of 7. Han, Luke, and Leia were the heroes of my childhood, and for 30 years after The Return of the Jedi I was confident that in that galaxy far, far away, the heroes of the Rebel Alliance had restored the Republic and fulfilled their epic destinies. Now, along comes JJ Abrams and Rian Johnson and Kathleen Kennedy, and they decide that the heroes of my childhood should be rewritten as failures. Their failures don't just present challenges for Mary Sue and the millennials, they practically invalidate their triumph over the Empire. A new villain indistinguishable from a Sith Lord has created an even bigger Death Star and crushed the Republic, dominating the galaxy with his New Order which is indistinguishable from the Palpatine's Empire. It's not that new challenges have arisen, and the heroes need to rely on a new generation to face the threat together. No, its that the exact same threat has returned to invalidate whatever victories you thought the heroes had achieved, and a new generation needs to learn from the failure of the last one.
I'm also not at all enamoured by the JJ Abrams signature clumsy misdirection thing. Either Snoke is not permanently dead (perhaps because of some Plagueis thing) and we'll get some idea of who he is, where he came from, and how he brought about the resurgence of the Imperial Remnant as the New Order, or this new trilogy has made a super-powerful dark side master a generic villain. Either Rey's parents are much more than just baby-selling junk scavengers, or there is no legacy of the Skywalker lineage. In other words, either we got a load of clumsy misdirection (and outright trolling) or the whole story of the trilogy sucks.
Now, I know Rey is, on some level, supposed to be a Skywalker. Force users can come from anywhere, but the two most powerful force users we've ever seen are probably representative of the two sides of the Skywalker legacy. Also, The Force Awakens was pretty blatant about it when Kylo goes poking around in Rey's mind: he sees her driven by longing for a reunion with her family, and comments on the related dreams of the ocean, and the island. Unless Rey is related to the keepers or the porgs, she's got to be kin to Luke. Similarly, introducing Snoke as a character who has apparently survived multiple mortal wounds (including having his head cracked open at some point) makes it seem less unlikely that simply cutting him in half will keep him dead for very long. That's what I mean by clumsy misdirection--neither Snoke's abrupt bisection nor Rey's "you're not important to anyone but me" ancestry revelation are persuasive (to me,) but I also can't really claim to have much confidence, at this point, that this plot will be redeemed in the Episode 9 instead of just going all in on the "wipe out the past and start fresh" thing.
As it stands now, Han died for nothing, Luke is an emo ghost that died without having actually trained anyone, and Leia is the leader of a support group for survivors. And that's not cool.