Re: Rey’s ‘power level’: I think a lot of the disagreement comes from a difference in understanding of how the Force is supposed to work. A lot of Yoda’s teaching in ESB - ‘size matters not’/‘only different in your mind’, ‘do or do not, there is no try’, telling Luke ‘that is why you fail’ in response to his disbelief over the X-wing being lifted out of the water - suggests to me at least it’s more of a binary thing than a linear power scale. Yoda wasn’t entirely just screwing with Luke, right, he really did think it could’ve been possible for him to lift the X-wing himself after what is, in the most generous interpretation of ESB, absolutely no more than a month of training, so long as he truly believed he could do it. After all, that’s how Luke wins in the first movie: he’s had less than an hour or so of training by Yavin, but the whole idea of the climax is that just by truly letting go and putting absolute faith in the Force, he lands the shot. Not because he’s spent six years training in the specific technique of Force-Enhanced Torpedo Accuracy.
Yes, but this argumentation ignores the fact there is some four years between ANH and ROTJ. In ANH Obi-Wan teaches Luke some basic stuff about the Force. By TESB Luke appears to have continued honing his skills over the years between the first two films, but it is unclear if Obi-Wan continued guiding Luke as he did in the final act of ANH. In any case three years have passed and Luke is able to grab his lightsaber with the Force with some difficulty under duress. Luke goes to train with Yoda for some undefined period of time, and subsequently gets his *** handed to him by Vader. Another year of honing his skills sees Luke reaching his potential in ROTJ.
Now let’s look at Rey’s journey, which sees her being pretty much on par with Kylo Ren by the end of TLJ, lifting tons of boulders, over a time frame that seems to be just a few days. There’s no guidance or training apart from a few lessons from Luke, who was intent on teaching Rey about the failings of the Jedi. When I see Rey’s development I’m reminded of a scene in My Cousin Vinny:
"Vinny: [Walks over to Jury, as he prepares his next question] So, Mr. Tipton. How could it take you five minutes to cook your grits, when it takes the entire grit-eating world twenty minutes?
Tipton: [nervously] I dunno. I’m a fast cook, I guess.
Vinny: I’m sorry, I was all the way over here. I couldn’t hear you. Did you just say you’re a fast cook? That’s it!? Are we to believe that boiling water soaks into a grit… faster in your kitchen… than on any place on the face of the Earth?
Tipton: [faltering] I don’t know.
Vinny: Well, perhaps the laws of physics cease to exist on your stove! Were these magic grits? I mean, did you buy them from the same guy who sold Jack his beanstalk beans!?"
The ST treated the Force like super powers. Once Rey realized she was Force sensitive, poof! she was an instant Jedi and able to pretty much effortlessly access powers others struggled with for years.