This is my second best team for P3 so far after JKR, and it's not that hard to set up. Revan's AoE will typically bring all the sabers below 50% health, then Sion and HK kill them with their AoEs. Traya will have Deathmark for the entirety of her topple, so Revan can do a lot of damage. Never had to do stand alone.
Granted, this is only tier 6, and it's likely not the optimal team, but the difference between tier 6 and heroic wouldn't be that big if the team was maxed out, right?