I don't have much experience with head textures. Even though, I just had to try a head texture of Derpy Hooves from My Little Pony. It's a 512x512 head texture on a 256x256 texture.
I'd appreciate any tips on how to catch this character's personality more or more details that I should add in. You can also see it in-game by "/dl Arbalest" and "/lp Arbalest"