Don't ever really need an actual healer, the NPC healer does a dam good job imo

(not only does it heal you, it heals others in the group and the npc's heal each other also)
infact you can do that last boss... having some NPC "tank" tank the boss down stairs, have ranged sit up top and just mash buttons... never get hit, and have someone kite the 2 adds (she won't summon any more), killed her pretty quick without anyone really taking any damage or even having to move.
Too bad the Lv34 instance boss, you can't cheese it the same ;/ That and the dragon boss hits about 3-4X harder with its attacks, and it easily has 2-3X the hp of Lv 38 boss (and also summons adds constantly). Shit soorta hits the fan when theirs.. 1 demon giant general thing, 4 summoned fire pillar demons + 6-10+ imps flying around, and the dragon aoe stun + poison puddles everywhere (he starts rage modeing or something around 25% hp and does a new 3 way poison puddle attack with varying range, no warning circles to show you where he's firing a big circle of poison)
I kinda want to see more instances like it, that shit is hardcore