Darth Sidious: Post your single idea to make him useful again

Remove the "25% chance to ignore armor" on his basic, replace it with something useful, like stun, ability block or TM reduction. Then make his omega do 50% of whatever that is.
You can't land a critical hit if the attack ignores armor (verified with Sid having Advantage - he does 3.9k instead of ~6k and retains advantage after his turn; normal damage is ~2.6k). It's completely contrary to his leader ability which boosts crit damage and chance.
Or, just allow critical hits on attacks that ignore armor.