So are Phasma's and Rose's buffs good enough to undue uselessness?

The more I think of it, the more I’m convinced her Omicron could just be folded into her Zeta and apply to all game modes.

Anyway, Jedi Training Rey, BB8, Holdo, Rose, and you can get away without a fifth. Holdo uses her AoE to put Expose on multiple opponents, burn down targets one at a time and don’t crack the extra exposes if you can avoid it so you keep feeding TM and boosted offense.

Don’t use Rose’s first special in this case. Her basic and stun are all you need.