For context, I recently got my Thrawn to 7*. Hera, Ezra, Kanan, Zeb, Chopper, all uniques omega'd and level 7 abilities beside. All except for Ezra were gear 8, with him being at 10.
Ezra was fastest, with 193 speed, 216% crit damage, and 48% crit chance, and an offense cross. To say he carried would be an understatement.
Hera was modded for speed and health, with 179 speed and 49% potency.
Kanan had pure health mods, 123 speed and 42500 combined health and protection. He did have his taunt omega'd, just so it could be used more often.
Chopper had full defense mods, 169 speed and 27600 h&p. I recommend tankiness so Kanan doesn't die, his offense down is crucial for dealing with the Deathtroopers and having him to taunt when it's just Thrawn is ideal. Trading taunts will be your friend.
Finally, Zeb was a potent boy. He had 139 speed, but a solid 71% potency. He had more h&p than chopper, since his survival is key for the fight. Think around 28000 for him.
Kill order is, of course, DTs, Commanders, Trooper, Thrawn. With Ezra at g10 it was super fast, as he just ate through them, even after Zeb died.
Now for the moral. I have been trying at this since I 7* my Phoenix, and I must say I was ready to throw in the towel. But I knew it wasnt going to last forever. So I persevered, and came out with a nearly clean victory. Tier 7 is terrible. Preloaded turn meter out the wazoo makes it impossible to get a clean start, and who Thrawn fractures first is the key factor in the entire fight. While I could have just waited, reliced my Ezra cause he isn't a bad jedi, and brute forced the event, where's the fun in that? Moral is, don't give up.
Can't wait for trying to beat 3po with gear 9-11 ewoks and chewie with gear 11 bhs.