I saw The Force Awakens at the theater and appreciated the humour of portions of it, but in retrospect I disliked more than I enjoyed about the film. I'm sure none of my opinions are particularly original, especially considering how much has been said and written about the film since it came out, but here goes.
The original characters are also undermined by this film. Luke is nowhere to be found; we find out that he committed the exact same mistake as Obi-wan Kenobi- training an apprentice who went bad. Again, this is the retreading of old ground: the talented Jedi apprentice who turns to the dark side and kills all the other apprentices. Exactly the same story as that of Anakin Skywalker. Apparently Luke responded to this by going off to become a hermit. Very responsible. More on this in my review of The Last Jedi. Speaking of a lack of sense of responsibility, let's talk about Han Solo, because this movie really does a number on his character.
So those are the ways in which I think The Force Awakens fails as a sequel; I'll write a secondary post on how I think it fails as its own movie as well.