Took your advice and went gnome bloodmage for my last run. I keep forgetting how strong their sanguine ability is. Was rocking ~52% health after taking down the Avatar, and had fun steamrolling the minions alongside it.
I really should play bloodmages more. I never used them much in my initial playthrough and only recently realized just how strong they are if played correctly. Anyways, time to rainbow stuff with the rat.