I have all FO toons G12, fully Zetaed.
When modding you want to run all Critical Damage mods aside from FO Officer usually. He needs speed mods so he can usually go first. More important than the Critical Damage mods.
With Advantage being passed around so much the choice of 2 Potency or Defense mods are up to you including Critical Chance but your FO team is always going to pretty much score Critical Hits which makes a Critical Chance not as important. Get as much Protection and speed secondaries as you can. Preferably Critical Damage Triangles with speed.