That's a problem with all the races in Trek. They're all stereotypes. Almost all Klingons, Romulans, Cardassians, Vulcans act as one. They almost always have the same hairstyles and clothing.
A Klingon would probably say the same about the humans though. All similar looking people in jumpsuits.
I love the Klingon's whole honor angle. Plus it's given even more depth in Redemption when we see Worf's idea of being a klingon is different than the norm.