CLS last unique zeta (all if you want to go all in is worth imo)
R2 both zetas are good
Maul and savage zetas for sith
Veerz Zeta for troopers
Asajj unique and lead, Daka unique, Talzin lead if you have her for Nightsister.
Kylo Ren zeta for FO or in general
QGJ zeta for Jedi
Han zeta is one of the best
Thrawn unique is good, lead is good for empire
Bariss Zeta is an all rounder and causes a lot of rage.
Edit: would say Old Ben for Rebels but GK is a better tank so if you dont GK then Old Ben can be worth