I know it's getting late for this, but I finally had enough shards to do the tier 7 Thrawn event today. Beat it first try.
I really think Zeb and Chopper are the underrated heroes here. They both provide healing (protection and health, respectively). Chopper has that extra buff dispel to take off the taunt from the Stormtrooper in the back. Zeb not only has that protection up move to help Kanan or anyone survive longer, but he can stagger, which takes the buffs off of the Deathtroopers, and his Daze/Stun basic can help a ton in limiting damage. When it came down to just Thrawn vs Phoenix, Daze made Thrawn use his cleanse, or Daze + Stun took him out for a turn.
It's not damage you need here, it's survivability.
But again, I believe speed is the key. Getting your guys as close to 200+ speed will make the whole thing a lot easier for you.
