Interesting that I do not see any replies from casters.
As a Necromancer, yes I would play another class. In a hearbeat.
Pet classes are grossly underpowered (at least as far as level 20) as compared to pure DPS casters. I realize that my pet is supposed to compensate me for the lack of pure dmaage output thru my spells but, when the pet can't hold aggro nor taunt so as to reacquire aggro once its lost it, what good is having the pet? I'd much rather have 3x spell damage and just stand toe-to-toe with the mob and nuke it down.
As for my Bard, I love him. He- not my caster- is able to solo yellows and miltiple greens and blues (even group ones) without a sweat. He's great in groups, adding to stats, magic resistence, mana regen rate and attack speed. Great solo and great in groups- what more could anyone want?