Nice try but they would never raise Kenobi up to be a major character equal to the Skywalkers. Rey is clearly Luke’s daughter but if you want a plot twist, try this one:
So is Ben.
Yes, that’s right. I’m proposing that Ben and Rey are in fact fraternal twins separated at birth for their protection from this Snoke dude. Rey was placed with Max Von Sydow’s character on a desolate, backwater desert planet– sound familiar– while Ben was placed with his Aunt and Uncle – sound familiar again? Remember, the Skywalker family was built to mirror the Hero’s Journey that appears in most every culture’s mythology. I think Kasdan remembers this and is setting the pieces in place for the father to save the son.