Why is it not fine? We are 2 months into the expansion. Do you expect to already have all the stats potentially capped out?
I am not counting champ because I have also done it without champ.
You need one tank (can be Guard or Captain - I haven't done it with warden but I'm quite confident a proper warden can tank this).
You need one heal (mini or rk. I prefer yMini for that fight because of extra mits - adapting like I said)
You need 2 debuffers (LM and Burg - Haven't tried double burg)
You need 2 "dps" (can be whatever - if tank isn't captain, you might be forced to take a rCap for survivability)

So the only class that doesn't have a spot in this is brawler but are we really arguing about that? So out of 11 classes, 10 have a spot. Might be in specific specs but that's fine.
Once again, if you are arguing about B2 T3 just for the random OS and AoE, I think that's missing the point. Sure they can be tuned down a bit and arguably, they should to avoid stupid stuff happening but bugged out mechanics (blizzard/shadow puddle) and B3 being a clown fiesta are much more important things to fix.

Tuning down damage on B1 is fine but same thing, this being the only thing touched upon is ridiculous, I hope we can agree with that