I think it'd be awesome if you could change your hairstyle by selecting it somehow, and then letting it grow out/cutting your hair with a tool/weapon.
And if I'm a marksman, I'd love it if face paint would reduce the glare from bright lights/the sun while I'm aiming.

There is no mirrors as far as I'm aware in Skyrim so good luck with the haircut
PS: Elven ears don't grow up again if slashed by accident.

I'd like to customise my guy after the tutorial, but apparently it's been confirmed as a no-go. I mean, if you're on a PC you could anyway.