I would like to see an option for spell effects that are linked to the terrain:
Spell: Enchanted Forest (Nature - Expert Spell Book, Tactical)
All Friendly Units in Forest Terrain gain +10 dodge bonus from tree branches that move to shield friendly units from attack.
Spell: Quicksand (Earth, Tactical)
All enemy units in desert terrain tiles have their movement reduced by 1 for 1 turn per Earth shard.