If there is a problem with BLUDTOPOWA underperforming, and I would be tempted to say that it's overpowered especially when it comes to building piety or crazy low level boss kill strategies, it's that Bloodmages don't get nearly as much benefit from it as several other classes do (at minimum, Wizards, Sorcerers, Rogues, Warlords, and now Vampires). It doesn't have much synergy with the other Bloodmage abilities. But they're not alone; Warlords, Assassins, and Paladins aren't the best at using their own glyphs, either.
On an unrelated note, in a peculiar way LEMMISI is actually weaker now than it was before. It used to be a reasonably useful glyph to spam with Mystera for piety (if you didn't have BLUDTOPOWA and didn't have some other glyph that can be spammed). Now it's much more inefficient since it earns less piety per revealed tile than any other glyph (1 piety for 3 tiles, compared with 1.5 piety for 3 tiles previously and 1 piety per 1 tile with BLUDTOPOWA and any other glyph).