Have seen this twice now, first watch I really thought that Rey might be Luke's daughter, but my second watch I am leaning more towards her being a child of the force sent to bring balance once again similar to Anakin. I also think Kylo Ren may cross over between good and bad through this trilogy, he was very conflicted in TFA.
I liked the fight with Rey and Kylo, she was definitely going to kill him if it wasn't for the ground cracking and splitting them up. She has a lot of anger.... Interesting indeed.
The shot of her walking through the dunes of Jakku with BB-8 though was one of my favourite shots in the movie.