So you know how there was a 4th lane in Dragon's Stand that got cut because it made the meta too clunky? And supposedly it was run by the Nightmare Court instead of the Pact, and that's why you find Duchess Chrysanthea on the islands at the end?
Shorten that up, cut it down for a 5-man PUG, skin the players as Nightmare Court sylvari, and that would be an awesome fractal. You could call it Court's Stand or something. It would fit right into the "historical" fractals family of untold stories, unseen perspectives. Maybe the NC did some things behind the scenes that enabled the other 3 lanes to succeed?
I just think it could be quite fun.