I do the event portion on the stairs, with totems on the ground at the base of the stairs.
Usually I don't care if the adds get to the floor, although killed them all on the stairs the first time for the achievement.

Pretty much have one fire elemental out at this point.
And pick up elites with the pally tank.

Novos becomes attackable, the whole team runs at him.
I switch to Frost Aura at this point.

I drop 3x Healing Stream and 2x Fire Elementals when I'm close to him.
And then just spam 1 (96969) on the pally, which is also the click dps for 3x Elemental and 1x Warlock.
When I need it, I'll 3x Chain Heal the lowest toon, and then have the shammies go back to dps.
This has always been a pretty easy one for my composition, one-shot it on the first try.