I like the concept, Can see that you have put a lot of effort into this one. Personally I don't think Bard will fit into WoW, at least at the moment but some of the abilities I can see being cool in game. I do like your idea of minstrel abilities that buff players rather than flat out heal.
I think if we are going to see a new class it will likely be one of the already existing NPC classes that we don't have like, Necromancer, Shadow Hunter, Battlemage etc. (Shadow Hunter / Battle Mage future ideas for you?
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