Body Scars! I want so many!
Body Tattoos would be cool too.
Tattoos for specific areas of lore or racial tattoos or class/job oriented tattoos that you can unlock would be especially neat.

I'm a suncat and I would love the option to have some fangs. even just little ones.

my xeala alt would look amazing with black scalera.
I know a bunch of raen girls would like to also have blue tongues like the guys.