I actually found the 7 star battle to be a bit easier than expected.
I have gear 11/10/10/9/8 for Ezra/Kanan/Chopper/Hera/Zeb (in that order), and I beat it first try without any issue. Zeb was barely a G8 too, with only the easy gear in G8. Pretty lackluster mods too, I just threw in my garbage mods that I don't really use anymore just to start with, and was expecting that I would have to re-mod to beat it. I omega'd Ezra and Kanan unique, Ezra basic, and Hera leader. The rest just base level. Only real strategy was making sure to use Hera's auto-raise ability after Kanan taunt, and then once I taunted with Chopper when Kanan was low, and without Hera's buff up. The rest was akin to auto attacking.
Maybe you just need Ezra up to lay the beats? I was kind of sad that it wasn't much of a challenge, and wish I hadn't sunk so many MK3 Carbs, and perhaps even the omega's, into my phoenix team. Glad to have Thrawn though, as an Empire fan. Good luck to you all!