The obvious choice is Palp and Thrawn instead of KRU and RG then you will have a much better squad by a long long way, but they both require rebels (Phoenix) to obtain and that might not be suitable if you dont have them.
If you dont have them i would switch out RG for Storm Trooper for sure, RG just doesnt offer enough in my opinion and if you get stuck behind a taunt his stun is useless. RG is not viable late game. KRU could be replaced with Snowtrooper or General Veers, this would give you a way better base for an empire squad IMO
Thrawn and Palp should be the priority for many many reasons, but if not then a combination of either ST, Snowtrooper or GV in for KRU and RG is my opinion!