Story, narrative structure, and themes were a lot more interesting than maybe any other Star Wars film. The remixed Empire elements were much better- and more-thoughtfully-used (and more-subtly-) than VII's retelling of IV's plot. Despite including those elements, it took a lot more inspiration from the kinds of sources that went into the original Star Wars movie than the other two in its trilogy do, rather than leaning mostly on other Star Wars films and mainly including a kind of filtered-through-previous-Star-Wars version of those influences.

IMO its biggest flaw is that the climax goes so entirely counter to what been foreshadowed hard the entire film, and cuts off any of several directions that alternative-version of it might have gone that would have been much better as far as storytelling possibilities in IX. I mean the part where Kylo offers to partner with Rey and she flatly rejects it. Almost any other way for that to have gone would have been more interesting and fit better with the way the film had been heading—Rey makes the offer to Kylo but he rejects it in favor of a face-turn; Rey accepts it; Rey rejects it, but because she doesn't trust him and wants to take over herself (to "do it right", of course)—anything like that would have been better. It's either a weird miss for the writer, or studio meddling, I reckon—and I'd bet on the latter, because damn does the rest of the script feel like it's going that way, to the point that I was kinda dumbfounded when it did the most boring possible thing instead.