[Illuminated One]

Well, what I would change:

Expand the scripting posibilities but at least add a keep casting that specific spell (at that kind of target). The 5 slots are easily filled by buffs, which doesn't allow effective spell combinations with spells the AI doesn't use correctly.

Research is generated by labs (but must still be paid for on a point for point basis, but the number of labs determines the max possible). Different nations get different research per lab/gold ratio, drain affects it on a percent base. Mages are only recruited for combat/rituals/forging and can be disbanded.

Labs get a limited amount slots in that gem/research producing items must be placed in to work. Initial Number of slots is depending on nation or god and can be expanded a couple of times for an increasingly larger price.

A player gets more control over random paths depending on how "institutionalized" magic is for the nation/mage.