Why does Rey have to be related to someone?

The only related characters out of the dozens in the OT were Luke Leia and Vader. We already have a relation in Kylo so why must Rey also be related to someone. Do we really need every character to be related to someone? Does Finn need to be related to Lando or Mace Windu?

I find all the theories on Who are Rey's parents kind of annoying because TFA really did not give us much to go on so it could literally be anyone or no one. Which makes all the speculation empty.

If Rey ends up being another Skywalker it is going to be predictable and not very satisfying. But if she is not a Skywalker it is going to be pointless, unless they somehow intend on not making her the main character; or if they plan on changing the story to not about the Skywalker family anymore.

It just feels like lazy mystery for the sake of it that will ultimately led to a unsatisfying conclusion.

Edit: I also feel it worth mentioning the ROTJ revel that Leai was related was absolutely stupid and one of the worst parts of the last film (the other being the Ewoks). It screamed of contrived plot to tie up lose ends because Lucas decided he wasn't going to do a sequel trilogy so he just closed the book on the "there is another" at the end of ESB. It really was a rather pathetic attempt to top the "I am your father" revel too. Everything about it was terrible. Rey being another Skywalker I think would be even worse especially since they went so much out of their to show her off while making just so unique and mysterious. God every time I think about how crappy her character (or lack there of) was i get so annoyed; especially since so many people liked her. I really do think she is the worst written and developed character ever (i mean JAR JAR has more of a backstory and character development then her).

". The buildup was intentionally intense to keep fans talking about it and theorizing and anticipating the next movie. "

I am not against this practice in theory, but they way they applied in TFA I think really hurts the narrative. We are literally left with nothing to go off of and all the theorizing is just empty speculation which i find annoying and frustrating.

It is like getting a puzzle that has a majority of the pieces missing for 2 years.

"If she's not related to someone significant, that is really terrible story telling, and may fans are going to be po'd."

right this is what I am saying; the character as I see it now must be related to someone because she is not complete or interesting enough to be able to stand on her own merit. Also no matter what the answer is not everyone will be satisfied. i think if the answer is too simple (like she is a Skywalker) it will feel underwhelming and unsatisfying. If it is too complicated (She is Palpatine's daughter or some miracle of the force) it is going to have the same effect that space jesus anakin had in TPM.

"I see no reason that Rey is not related to Luke Skywalker."

We already have Kylo related to Luke. Does every character have to be related? Can no one stand on their own.

"Why does Rey have to be related to someone important??!!! Because the main films are called the Skywalker Saga. If the Skywalker are not the focus, then it's a spin-off, which the episode films aren't."

I'll say it again, KYLO IS ALREADY THE SKYWALKER; does every main character need to be one? Obi-wan was not a skywalker, Han was not, Qui-gon was not, yoda was not, Lando was not, Finn and Poe are not. In the PT only Anakin was a main character was a skywalker. In the OT we did not find out about Leia until the last (and it did not help the narrative).

"Rey is a Skywalker."

What if she is not? what if she is a Jinn; Kenobi; Palpatine; or any of the other ridiculous theories I have heard? what if she is not even the main character and it is actually supposed to be Kylo? And if she IS a Skywalker why keep it a secret because ultimately it is too simple and predictable to be a satisfying mystery?