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.
It’s certainly possible to construct a reasonable argument demonstrating that Rey’s use of the Force isn’t necessarily so different from what we see in the OT. Both the OT and the ST play fast and loose with elapsed time. We don’t know if Luke was training on Dagobah for a few hours, days, or months.
But the problem with Rey is both one of degrees and writing intent: The OT clearly indicates Luke needs a mentor in order to learn new Force abilities, and he seems to acquire new powers incrementally with training. But Rey appears to acquire new Force abilities spontaneously and rapidly, without any mentor or training. Luke needed Kenobi to prod him along to deflect blaster bolts and later blow up the Deathstar. In the cave on Hoth, Luke struggled to perform telekinesis - we don’t know how he knew this Force power was even possible, but the sense of elapsed time that passed between Episode 4 and 5 leaves open many possibilities. Then in Episode 6 Luke seems much more powerful. A few years have elapsed since Episode 5, but it’s unclear how Luke grew in power, since he apparently didn’t return to Yoda.
But these fuzzy ambiguities about Luke’s training likely result from logistical problems with the writing rather than what the films were actually trying to convey about the Force. Episode 5 seems to want to convey that Luke was on Dagobah for a while, and mastery of the Force is a slow, incremental process requiring training, even though it’s hard to understand how Luke could have been on Dagobah for long given the overall plot logistics.
But with Rey, there’s not even an attempt to convey that it takes time and training to learn the Force. There’s a scene in the Force Awakens where Rey is being held prisoner, and she somehow spontaneously discovers the “Jedi mind trick” in order to free herself. Then after she escapes, Kylo Ren says that the longer it takes to find her, the stronger she will become, implying that she’s gaining power by the second! The next day, Rey is able to lift tons of heavy boulders with the Force. Rey’s learning to use the Force is depicted more like “unlocking” a latent superpower, and she requires little or no guidance from a mentor figure to acquire new powers. Luke’s Force abilities required guidance from a mentor, and were of a significantly smaller scale than some of what Rey does (Luke struggles to lift a single medium-sized rock in Episode 5). Some of the discrepancy between Rey and Luke is attributable merely to the normal Hollywood tendency to make everything “bigger and better” as special effects improve over time. But the writing itself also indicates Rey is rapidly “unlocking” new powers in real time, growing in power rapidly with no guidance from a mentor. It’s really at odds with how the Force is portrayed in the OT (and certainly in the PT), despite the way the OT often plays fast and loose with elapsed time leaving open questions about Luke’s training.
And despite Yoda’s “size matters not” statement, the OT certainly portrays learning the Force as an incremental process requiring training, where smaller scale things are easier to do than larger scale things. (And if Yoda’s “size matters not” statement is really to be taken at face value, why didn’t Yoda just fling the Death Star into the nearest Sun and call it a day?)