I did Dawn for the first time today and was able to do over a million points of damage at CR 76 and I had the lowest power in of the entire group. Not one of the CR 90+ was even close in damage. The name of my league is CelestialIsOP.
What is your loadout and combos? I'm a hardlight and I switched to celestial for 2 days and didn't like it much. I must have been using it wrong. I play with a very select few celestial dps that murder my damage out. Every other random celestial I come across can't even compare. Power out on the other hand I can't tell you...I don't play very power conservative unless I have too.
Your league names says it all, but other than that HL is the best power in the game for DPS but power in to damage out ration with celestial, now thats why its OP if it did that amount of damage with about of power it takes to dps with HL then thats perfectly fine.
I run with admonish, malediction, death mark, smite, plague, and the 33% life drain super charge. I combo everything and I am precision based. If you want to run might based reverse all the powers. My precision is 518 and my might is 1442. My point is the name of my league.