I beat Tier 2 for the first time yesterday with phoenix (sabine excluded). All G8, 7*, level 80+, omega uniques. No speed mods to speak of except a speed arrow on Ezra.
One thing I haven't heard anyone mention is to remember that the RGs won't stun once their health is in the yellow. My strategy was to suck up the stuns with chopper taunt while I worked each RG health bar into the yellow. Meanwhile try to stagger EP and then stun him using zeb (and calling zeb with hera and ezra). Set up Hera's revive on taunter if possible. That said it was still tough at these levels with EP one-shots; lost 3 toons yesterday and 2 today.