We'll probably nerf B2P a little bit, but happily enough the core idea seems solid.
Reckon the extra +1 mana on cast is a bit superfluous, it should still be a pretty solid glyph with the "normal" mana return, no?
And with regards to the LEMMISI domain overlap, I'm trying to figure out whether it should be changed to a "semi-smart" reveal (like LEMMISI, but fewer priority tweaks) or a simple "reveal closest tiles possible" rule (the current office favourite, and since the glyph has turned out to be powerful enough it shouldn't be an unacceptable move).