I've also seen two karmic greater vaults, too. In probably ~500 games of 1.0.0. So can't really tell yet whether they exist in the current versions. :)
But yeah, it would be cool to have more different kinds of greater vaults, such as:
Golems (clay, stone, snow, iron, steel, diamond, eternium)
Demons (quasits, lesser demons, greater demons, fire/water/air demons, molochs, one balor)
White, blue and black dragons
Unlifes (stone snakes, gargoyles, animated armors, living walls, earth elementals, one greater earth elemental)
Minotaurs (ancients, mazemasters, mazelords, mages, a king)
Jellies (all kinds, also death & stone oozes)
Chaos creatures (chaos servants, greaters, corruptors, annihilators, chaos warriors/wizards/warlords)
Also I'd love to see a doppelganger vault, but that would probably fit better as a lesser vault. :)