Spell casting routine is seriously screwed?

[K]

My games have shown that the AI doesn't want to cast spells with a final fatigue over 200. Even with spells with a final fatigue between 100-200 are sometimes not cast.

Communions, gem boosting, and just having enough levels in a Path to reduce the fatigue down are needed to get the AI to do what you want.

Also, the AI wants to cast self-buffs on turn 1, and get progressively more sketchy on turn 3 and after. Cast your big spells on Turn 0 or Turn 2 if possible.