The way I look at GAC is which squads generally do better on DEF.
For me it’s DRevan North, JRevan South.
Also mods play a HUGE roll.
Example; I use a Helmet Squad along with DRevan so I know they will be hit 1st.
( Veers, Starck, SnowTrooper, MagmaTrooper, StormTrooper. )
I have my Storm setup with 4 Offense, 2 Health but along with Def/Tenacity secondary perks so he can take a hit while taunting and not get a debuff.
My SnowTrooper I set up for pure Crits due to 1 of his specials.
Biggest advice is use mods to play off what you want that character to “ specifically “ do while in combat. Sure DEF Squad follows a gambit system you can still alter it some due to mods.
Some examples I say ( opinion ) are good for DEF squads are IMPERIAL TROOPERS lead by Veers, FO Lead by Kylo UM, Ewoks ( very underestimated squad ) and Both Revan’s, Bounty’s. ( BHs to me are the JACK of all TRADES meaning they have a Lead for just about anything and can possibly beat any squad. )