The 'Lighter' Side Of The Force
I think your last theory is correct, though you had some holes in it. Luke had kids with Mara Jade, she died in combat, etc etc, you pretty much have it down. Though It still is possible for her to be Han's daughter, because Han and Leia had three kids, two sons and a daughter, but all that I have said can be thrown out the window because Disney declared all that non-canon.
Your theory for Luke being the father works for Han as well. Leia was pregnant and Han left so he never knew. Plus you said the story was about the Skywalkers...last I checked Leia is a Skywalker and if Han and Leia are the parents that still continues the story.
I'm still partial to the Rey = Anakin (reincarnated). She's technical whiz with mechanical stuff and even fixes the Falcon. She can understand droids and other languages naturally. She's an amazing pilot, almost like she's done it before, even though she's never left Jakku. Anakin built that light saber. The saber calling out to Rey would bring the weapon full circle back to it's original owner if Rey was indeed Anakin reincarnated. Why would the young Obiwan voice be used during the force vision? That vision may have been more memory than vision. Using the older Obiwan voice in addition to the younger Obiwan voice reflects the duality of when she was Anakin, and when she was Darth Vader. Palpatine dangled the idea that Anakin could defeat death through the force, and, Anakin may have learned that secret much later.
I like this theory the best!
Geez why do people always try to connect characters? Maybe Rey is just a brand newcomer in that galaxy far far away, among billions and billions of other people, and maybe her parents who abandonned her are just random parents and not known to the public. The force can appear from anyone, not always from the same families. If it is revelead that Rey is indeed a perfect unknown new character, people will have to get used to it and stop making crazy theories like "she'z [INSERT RANDOM FORCE USER CHARACTER NAME] dauter cauz she has ze force duuuuuh!"
She could be family if some prequel council member. Who cares she's bad ass.
I guess we are going to have to wait until they show it on Maury... and _____ you are the father.
I like the theory that has Luke hooking up with Obi-Wan's daughter, thus making her a Kenobi and a Skywalker. This would allow many of the cool connections to be made, times two. Additionally, it would explain the ridiculous amount of power she has with the force, despite being untrained whatsoever.