Seers can potentially stack mezzes to stun LTs/Bosses I think too, which is why they are the lowest dps pets.
Personally I usually do BP on most of my 50s, with at least a T2 Longbow Cataphract to swap in for the -regen for AVs unless I have it from somewhere else. BP is ugly as sin though, Carnies and Knives of Vengeance untouchable LTs have good buffs iirc