Hickman is my favorite comic book writer. LoSH is my favorite comic book franchise. The pairing is pretty much my ideal. Its my dream writer on my dream book.
Apparently Hickman was just about to do it, as he attended a DC writer's retreat or somesuch. Also, apprantly he proposed a lot of writing ideas (involving the Legion and Lantern Corps, I heard) that he eventually used when he hopped to Marvel, incorporating them directly into the Krakoan X-Men stories. I heard is caused quite a bit of grumbling at DC, since they already made future plans with his ideas, which they then had to abandon.
It isn't much of a stretch to look at what Hickman did with Moira McTaggart, then look at what Bendis did with Rose/Thorn, and see that Rose/Thorn was probably supposed to be the Moira of Hickman's original Legion story for DC.