[RKDinOKC]

So here is the most direct synopsis
Top of the force was...
Snopes = Luke
And they were replaced by...
Kylo = Ray

Snopes even commented that he had warned Kylo that the stronger he got the stronger his light counterpart would get. They are shown as equals when Kylo and Ray had the light saber gimme draw.

Luke went into exile when he not only realized he was training the next dark lord, but that Kylo was going to be even stronger than Luke OR his counterpart. That is why he talked about balance to Ray and a bit freaked when she did not hesitate when the dark place at the Jedi Temple called to her. Luke didn't seem to remember his dark place visit under Yoda's training where he became his father.

Be interesting to see where they go from Ray's visit to the dark place where looking for her parents the two shadows became her. Very much like Luke was looking for Vader and saw himself.