Yea, I never said the Kenobi theory was actually realistic, I just love the idea. And also, the theory isn't quite as weak as you would think. Obi Wan had a lover in the clone wars series, but because Obi Wan was more loyal to the Jedi code than Anakin, as well as some other things, they never had the chance to become a real couple and ended up spending a lot of time apart. The theory is that he knocked her up, and in the time they were apart, she had a child before she died in the Clone Wars, but never told him about it because she knew it would be a big struggle for him because of his loyalty to the jedi way. Now, this child wouldn't be Rey. It would be Lor San Tekka (the old guy at the beginning of The Force Awakens). His age most likely puts his birth sometime in the middle of the Clone Wars. In this theory, Rey would HIS daughter. The real flaw in the theory is that there would be a big plot hole because he is on Jakku, and Rey is "waiting" for her family on Jakku. The theory is strong that Lor San Tekka is related to Obi Wan, but once you throw Rey in, that's where it falters. Not a good enough theory to be a real contender, but I just like the idea of Obi Wan's legacy being carried on in the main series.
I don't think they would ditch the Skywalker family. The whole story is supposed to follow that family. However, Kylo Ren is technically a Skywalker, so I don't like the idea of Rey being one too.