I still don't think the truth of Rey's parentage is quite as cut and dry as this movie presents it. I don't think we will find out she's a solo or Skywalker or a Kenobi...But there is more than what was shown here. My theory? She's a child or sibling of one of the students Luke was training at the temple. Now, not having read much of the new canon I'm not 100 percent sure if this is the same now, but in previous EU Canon, some of which HAS been adapted into the new timeline, not all of Luke's Jedi students are children. Some are adults and older teens like himself. Notice that in both TFA and TLJ no one specifies the ages of all of Luke's students. What if in Luke's recruitment travels he met someone who was adept with the Force and he offered to train them, but they had a child or a younger sister they had to care for? Perhaps he allowed this person to bring the girl with them to where he had his temple. Perhaps there she befriended some of the other students, including young Ben Solo and she even knew Han and Leia, who I'm sure may have been regular visitors. That would explain why not only does Kylo seem to know about her, but why also Han gives off a vibe that he knows more about her than he was letting on and was even slightly protective of her. So...How does Luke not know who she is the moment he meets her? Two possibilities... One is that in the chaos of the destruction of the temple, Luke assumed she died, but in reality Kylo took her with the few of Luke's other students he didn't kill and , because he was fond of her and wanted to ironically protect her from both Luke AND Snoke, wiped her mind with the Force and dropped her off in the care of junk traders whom she thought were her parents. The ones who sold her for drinking money . Or... Luke finds young Rey amid the ruins of the temple, alive and tramatized. He briefly cares for her until he realizes her Force potential and fears that what happened to Ben could repeat. So , racked with guilt for what happened with her guardian ,he erases her memory of what happened at the temple, puts her in the care the Jedi historian we see at the start of TFA and tells him to take the girl far away and not to tell him where they were going, and to make sure he would never find Rey and train her himself, uses a mind trick on himself so he'd forget her, and then disconnected himself from the Force, until Rey returns into his life a decade later. Either way, it still keeps the integrity of both the " clues" in TFA whilst keeping the integrity of the reveals in this movie.