Oh brother...
I don't know when the magical day will happen but I will keep fighting untill people finally realize there's nothing, or very few things, on the server as "OP". Well, depends perhaps, if you duel against a 6kgs opponent being fresh 80, but whatever, I guess you are intelligent enough to understand my point. But let me tell you that I really found it hilarious you using the term "overpowered" when you usually play as 10 BiS multiboxer, oh the irony ;)
Human is good of course, I won't dare to say no, but one different trinket only over the entire gear is definately not anything to call it "op". Humans don't have meld (it's generally crucial as priest for example), aoe stun, aoe silence, haste boost or damage boost, I would love to have one of those honestly. In the end, things are more balanced and very situational, so, instead of being so worried about human racial, or whatever people may find it to be a problem, as I said, skill, coordination, etc etc are what they need to solve their own issues no matter which race do you play.
This is an obvious problem - "I can't beat it / I have problems with it --> It is "op" for sure!", and then they don't know how to benefit from their own racials, period.
About the fact that most hardcore PvP'ers playing human, you know that doesn't mean much, you'll notice even on crappy vanilla servers out there, most of alliance PvPers (and the big most) are also human, and PvE players even. Why, because is it better? No, because of its looks, simple as that.