TFA is, in context of the whole series, a sort of boring rehash of the OT. But it was 30-40 years later and was perfectly serviceable as a soft remake (I'm sure we prefer TFA to Abrams just remaking ANH?). But there's a lot of new stuff in TFA, namely Ben and Finn, that they really could have taken the other two movies to great places.
I didn't hate TLJ (only half or less of the film is good, but the good parts are really good) but I think it's the reason the sequel trilogy as a whole fell off the track. It would have been better either as the first movie in a trilogy or as the last, but it didn't want to use the board TFA set up and didn't seem interested that there needed to be something to come after. (While not the core problem with the film, the lightspeed kamikaze basically broke the Star Wars universe's internal logic in a way that it's hard not to think about when watching any Star Wars film, just for a cool shot.)
