Having re-watched the original trilogy, a few snippets of the prequels, and The Force Awakens prior to seeing The Last Jedi, I feel like, as a whole franchise...Star Wars movies are fairly mediocre.
A New Hope managed to take the entire world by storm, and define media and entertainment for a good chunk of the late 1970s/early 80s, and it tells a simple story well enough. However, it's a tad cheesy at times. It's a good first entry, with a some flaws dotted about.
Empire Strikes Back is, in my opinion, the best overall Star Wars movie. It has action, it has a crazy bomb drop of a twist, it has a cliffhanger ending, and it also has Yoda, and Yoda is the greatest.
Return of the Jedi is 95% snoozefest. The intro is way too long, there's those little ewok things that clog up the film even more. The ending, though, is awesome, and just about worth sitting through the other parts for.
In terms of the prequels, I've not seen them fully, only bits and pieces from reviews, jokes, and other snippets, but Phantom Menace seems a tad grating, Attack of the Clones is cheesy, and Sith looks to be actually pretty cool, and has some great action scenes, especially the last fight.
As for the new movies, I can't get into them at all. TFA had so many boring moments, and ridiculous writing, with sparse highlights (A Stormtrooper that turns rogue? That's cool! The new villain has ties to the original cast? Interesting!) but parts like Rey using Obi Wan's Force mind stuff with no training, Rei being able to fight a super Sith dude with, again, no training, one of the "main" characters, Poe, just kinda becomes irrelevant towards the mid half of the movie, Snoke has no character, etc. TLJ itself is a mess--Leia's magical whoosh through space, Snoke still has no relevance, random uprising plot with Poe that kinda doesn't go anywhere, stupid casino subplot, Luke's return being good or not is...debateable. The best part of TLJ, was the little brush off Luke gives in his fight. Beyond cool.
I'm not even a big Star Wars fan, honestly. I don't even enjoy a majority of the flims. But will I go see IX? Of course.