Klingons should be whatever it requires for the story at present. You could do hundreds of stories with Klingons but making them identical to humans is ridiculous since there's no point in having Klingons anymore if they're going to be humans since we have humans for that.
Are Klingons barbarians for having frizzy hair and swords? Not really, not anymore than humans are for their fashion choices. It depends on whether or not they can make warp coil.