I always wanted more diversity of characters front and center. No good reason there wouldn't be gay and non-binary people in a universe that large and expansive. I liked Finn and Rey in TFA, but they never got the development they deserved in the follow-ups.
I liked them both too. Finn especially got short-changed. Rey had more overt focus... but we really didn't learn a ton about her and a lot of time was spent on her being a Jedi. I know there's a range of reaction to TFA -- but the thing is, it basically set up the potential for character development. We saw them all, made a connection with them, and the following two movies should have been building off that to develop who they were. Instead we just got random crap that wasn't really tied to character per se. I am not interested in knowing who Rey's parents were (per se), for example, which is external -- I am interested in knowing who SHE is. And Finn got mostly a fruitless "fetch" quest and then resolved his plot arc with Phasma unconvincingly, and then had nothing to do in the final film.
I get the "Luke and Anakin are Mary Sues too" argument, but I am not sure it's true, at least in the case of Luke. He struggles, gets kicked on his ass, then learns from his defeats. His arc is an almost perfect realization of the Hero's Journey. Anakin is certainly one in TPM--most of the Jedi are Mary Sues thropughout the prequels, until they suddenly aren't about halfway through ROTS.
Rey had so much promise, and she's just so boring and one-dimensional. Things just happen to her. She just feels like a passive character moving from one scene to another rather than the crucial central character whose decisions can alter the outcome of the entire story. She could've had the perfect Hero's Journey trajectory but they just squandered so much opportunity.
I agree they focused more on Luke's development, as thin as it was. I like that he went after Vader in TESB, because that whole sequence was basically, "Luke has gotten really good and is trying to fight for his ideals; but Luke is also getting his ass kicked, and some of what he was told was a lie." So he has to try to deal with that in RotJ and work through his weaknesses.
I didn't mind that Rey had an affinity for the force, but she certainly didn't have or shouldn't have had any fine-tuning of it. But basically Johnson did little with her development in TLJ, except in context of Kylo Ren. Neither of them any longer had a script for their lives. Neither really had a family to define who they were. Both of them lost any authorities in their lives. They were really on their own. But then there was nothing about that in the final film, just hints -- like the big scene when she goes into the crashed Death star and supposedly is going to confront herself... but what came of that? nothing, really. Everything in that film was unearned.
Yeah, Rey was kind of a gopher. "Rey, go find Luke. Rey, convince Luke to help. Rey, go here. Rey, go there." Even doubling down on her relationship with Finn would have been good, but the only time she spent with him was fluff and/or fetch quests, really.
I was even cool with she and Kylo basically connecting as both being orphans / rejections, it's a pretty Gen X thing where you find yourself on your own and having to forge your own way. Except then TROS abandoned it all and just put them back in the predictable thoughtless tracks, instead of letting them grapple with making their own ways.
The Matrix Reloaded did have a few good things, and one was the Merovingian's speech, about how knowledge leads to self-power. When you don't know anything, you are at the mercy of those who do -- you basically go here, go there, you are on someone else's agenda. To have autonomy, you need to know why you are doing what you are doing and/or be making decisions out of your own agency, not just doing what others direct you to do.