Theoretically instead of having Geomancy work by boosting Cleric Stance (because if you're making a DD out of your Conjurer we want you to take on DD gear instead of healer gear) you probably want Geomancy to be your MP recovery skill. An active that has some somewhat short-ish cooldown (40~60s cooldown) that recovers MP in one of three ways depending on the element of the ntext spell:
Earth: Recovers a flat amount of MP based on damage dealt
Wind: Grants a stronger Refresh effect, shorter-lived than Shroud of Saints but more powerful
Water: Creates a rather weak Refresh Zone, that refreshes MP as long as you're in it. Aids allies too.

Theoretically you would want to always be under effect of two of those, and since multiple copies of the same don't stack