Hmmmm there are a few....

Probably the Astragoth (Chaos Dwarf) Cool robot body, check, Cool magic powers, check! Turns to stone, darn it,

Orion (Wood elf) King of the wood, big strong, giant (hur hur) horn, oh no, its winter - time to suck, and of course his role in the end times....

Tyrion (High elf) I want to love this guy, he's awesome, just seriously, slap your brother and go your own way.

Death master Sniktch (Skaven) OK we get it, master assassin, ubermensch etc. just get owned a bit, just once? I mean you're not even trying anymore!

Grom the Paunch (Boblin) Niblet was way cooler

Arbaal the undefeated (Khorne Chaos Warrior) - ironically, ALWAYS defeated!