Although I don't mean to offend, my point is you don't have a story idea. Its not that you don't love Star Wars or don't think deeply about Jedi Philosophy. I think you don't have a story idea and what you replied to me above proves that.
You are saying there are a ton of story ideas around your Kylo/Rey as Grey Jedi pair, however, you haven't suggested any such ideas on your own. Instead, you suggest your concept, which is more of a philosophic concept than anything, and suggest exploring that, rather than a plot line.
You admitted in the earlier post I reacted to that you didn't know how your idea impacted the storyline but you weren't hot on the entire plot-line from TFA.
The sort of story ideas you could come up, on the premise of having two members, already embedded in their respective positions, saying "screw this" and going off on their own, are not likely to be very good story ideas. It is more likely that any story on this premise is going to transparently and heavy-handedly shift away from the plotline to something completely different.