I don't see any mention of Pugnacity, it should be ALWAYS on when dealing with non trivial content. You should've taken exploratory surgery, which means every UM grants upper hand. So the first time you use UM, immediately hit Pugnacity, and make sure it won't fall off. If the there's too much damage, run your energy down and hit Cool Head at 20 energy.
Remember if the group wipes, all the energy in the world do you no good.
Also make sure your group uses crowd control, you won't believe how much easier even if 1 out 5 mob is CC'ed.