Sith trooper does not die. Mine is G10 (still 3*). With mods he has ~21k hp and ~39k protection. He almost always lasts the whole arena match without losing protection - his defense is insane and still gains Zaul's dodge bonus.
Right now I have him modded for as much protection as possible, but once my SA (G7 now) is ready for arena, I may mod him for more crit damage to help SA knock toons below 50% hp to feed savage. At G7, SA seems to be able to hit for ~10k damage on crit under ideal circumstances.
Team I'm running is Zaul, EP, Savage, Trooper and B2 (SA in a few days). I think savage really needs a Zeta to make this team top 10 viable on my shard, But not sure if next zeta should go to savage or Kylo.
Edit: for clarification, almost everyone in top 20 of my shard uses some combination of baze, chirrut, or general Kenobi. Late December 2015 shard. I have none of the above
