Those are some good ideas. Recurring enemies would be great - I think there’s even a Stormvermin commander in the game files? Just give him a higher health pool, and the ability to run away and summon more Stormvermin . . .
Tail attack would make a lot of sense, would go well with the idea of having Clan Esshin elites around the map.
I’m torn on the idea of variants of existing enemies, though; so much of the gameplay is centered around learning the behaviour and abilities of the enemy units; mixing that up (while I think the idea would be cool) would be very challenging for newcomers.
