Maybe a bigger debuff when low on happiness or resources?

I suppose the Devourer Tank could be a Helicopter Gunship replacement that's slower but has a ranged attack and the Stormrider is a Jet Fighter with superior stats?

And for the Scrin civ itself...maybe they start with extra tiles and their borders expand faster on their own?

I guess the Threshold could be a unique defensive structure that can only be built in the capital and has a crazy amount of HP for the city.

no idea how to balance them tho

Scrin civilization? That'll be a first.
Also reminds me of some ideas I have for CnC Generals civs...