What we want is for something for blood elves that is a unique skin tone or something that is fucking visual to see when you are wearing full armour.
Jewelry which won't show unless your wearing bikini armour is rediculous. Hair styles are 99% the same when it comes to void elves having blood elf styles with a handful of their own. Much like having all the blood elf skin tones plus their own.
Essentially just give blood elves undead skin tones and red eyes to balance void elf void skin tones and void eyes. So both sides have something highly visual and unique. Not one side absorbing 90% of the other side plus their own stuff.