Who is Rey (2)?

Many people have complained that Rey being Luke or Han's daughter was too easy and that it would be such an obvious reveal in Episode VIII. So a new theory has emerged: could Rey be... Palpatine's granddaughter?

Okay, you might be thinking "this is going WAY too far, this is too far-fetched to be true." But this theory actually makes perfect sense...
In "The Force Awakens", Maz Kanata tells Rey that her parents "are never coming back". It would be odd that a force-sensitive character such as Maz say that Rey's parents are dead when Luke and Han, the suspected fathers, are both still alive. It is, therefore, improbable that Rey's parents are characters that appeared in the Force Awakens, they are most likely already dead. That would also explain why Leia and Han do not recognize Rey.

Chancellor Sheev Palpatine, aka Darth Sidious

Furthermore, Rey is a very powerful force user, which means that her ancestors were as well. But Jedi, according to the Jedi Code, were not allowed to be married or be in a relationship. Which only leaves us... a Sith Lord?

Peace is a lie, there is only passion.

Through passion, I gain strength.

Through strength, I gain power.

Through power, I gain victory.

Through victory, my chains are broken.

The Force shall free me.

The word "passion" is what interests us in the Sith code. Unlike the Jedi code (There is no passion, there is serenity), the Sith Code not only allows, but encourages passion, if not love.

So why Palpatine? There are many arguments to prove this point that will completely change the way you see Rey... (Credits to VincentVendetta)

First, there are their fighting styles, which are similar in every way. They are the ONLY known characters in the Star Wars universe to use the "forward thrusting stab". The battle between Palpatine and Mace Windu and the battle between Rey and Kylo Ren are introduced with this move:

This move is also used by both characters.

Rey's fighting style was inspired by another's, and it has to be the emperor's. The two battles are almost identical; in both cases, a Palpatine wins.
This duel is Rey's first experience using a lightsaber; however, she triumphs over a powerful dark side user (Kylo Ren) who has had many years of training. What if her ancestor was the one guiding her hand that night? You can clearly see the great anger that lives inside her, as she is drawing strength from it. She experiences a powerful pull to the dark side. In the official book version of the Force Awakens, it is said that Rey hears a voice in her head saying "Kill him" after Kylo Ren has been stricken down. Could this be her grandfather's voice, pulling her to the dark side, influencing her just as he influenced Anakin Skywalker during his fight with Count Dooku?

If this isn't a dark-sided influence, I don't know what it is.

Next, Rey and Palpatine are the ONLY two characters in the Star Wars universe to have an English accent. This is extremely significant, for J.J Abrams asked John Boyega (an English actor), playing Finn, to take an American accent, while he told Daisy Ridley, playing Rey, to keep her original English accent.
Furthermore, her abandonment on Jakku makes sense. We could assume that Luke (aware of her affiliation with the Palpatine family) took her to Jakku so that she wouldn't be found by Snoke who was trying to lure Kylo Ren to the dark side. Luke wouldn't want such a powerful force user on Snoke's side.

Rey being abandoned on Jakku, held by Unkar Plutt

Also, Palpatine's voice is in Rey's force vision! We hear very distinctly the words "...any Jedi", which is a reference to what Palpatine tells Anakin in Episode III: "Only through me can you achieve a power greater than any Jedi." MAJOR clue. Nothing to say here.

And finally, this plot twist would make the story so much more interesting! The Skywalker v.s Palpatine war has always been at the center of Star Wars (Luke Skywalker versus Sheev Palpatine) now imagine this: Kylo Ren-Skywalker versus Rey Palpatine! The Dark side would be embodied by a Skywalker, and the Light side by a Palpatine. The whole mechanics would be switched around, which is far from boring. Now we just need to see whether Rey is seduced to the Dark side by Kylo Ren-Skywalker, just like Anakin was seduced by Palpatine...