Snoke was actually explained in a book, but I'm not 100% sure in it's credibility. Snoke was a failed clone of Palps, but wasn't discarded because he was farce sensitive. Palpatine controlled Snoke through a ring on his finger that was in Vader's castle. Palpatine also never had a kid. Rey's dad was another clone that did not have force sensitivity, but survived the cloning process. He was going to be the heir to the Empire (no pun intended again) but ran away, fell in love, and had Rey. I would really like to see that explained in a show, not just a book that I don't even know the name of.