I can see a team like the following being effective
Finn
Mace after update
Fives
Aayla
Princess
Who do you attack first?
Probably Finn, maybe mace? But mace death will cause the whole team to attack again. But Finn and mace with expose and Princess for DMG. Finn and Aayla stuns (princess will help Aayla). Fives can be replaced but his health Armor and counter will have him and Aayla being left at the end of a tough fight and they should clean up between both of there assists and counters.
Fives and Aayla could be replaced with Plo or Poe. Plo defense up will help mace and his offense down will help everyone. Plo is the only toon who can mitigate damage with both offensive down AoE and defense up AoE. Poe is because he is Poe and Poe Mace and Finn exposing like Woah.
To the Devs: expose should override Stealth. Poe and Mace expose on random people is wasted and just by its Ability Name it sounds like it should. It would also create some cool counters to Invisible folks, instead of Just Plo as a leader and AoE teams.