[khorboth]

I don't have my resources with me but in brief what I did for arcane casters was:

Start with vancian magic and threshold magic from thaumatology.

No arcane caster got plant, animal, or healing.

Each color of robes got one college that was exclusively theirs and one that they were barred from learning.

Spells were divided into levels based on (prerequisite count)/2 with fractions dropped and max level was 9+. Each spell level was considered a different type for the vancian buying.

Then I created a "Package" of threshold enhancing advantages required to buy up to get access to the next level of spells with magery increased every other level.

Given the rarity of magic in world and the social reverence/fear a mage would generate, I just eyeballed it as a +0% on magery. I did separately require a vow for wearing robes and not using weapons, though.

Moons were just a feature of the world. It balanced out to 0, so no modifier.

I know this isn't quite the direction you were looking to go, but I hope it helps.