Also, in the ‘Awakens’ script & novel, it makes it very clear that Luke not only knows who Rey is, but that he’s extremely apprehensive of her presence. Some would say that means he’s afraid that she, like his father Vader, will be turned to the dark side. But what if what Luke fears is that her incredible abilities, such as when she splits a large rock in half (seen in the recent trailer), reminds Luke of the terrifying power of the Emperor.
And for the record, doesn’t the whole narrative that Rey is a Skywalker seem way too obvious? But Rey being turned to a Sith and becoming as menacing as her grandfather, now that’s a twist. I’ll go one step further, what if Kylo, who has fallen from Grace, is redeemed and turns good and has to be the one to stop and defeat Rey?!! Holy Hell?! Now things are getting interesting.