it suffers from the same problems as dengue used to have, stewie from family guy type faces, i made the same comment to him way back, he worked it out though. its just some slight proportion problems that happen on the sphere.

its mostly the chin and the angle from there. if you flatten/widen the chin a bit(flatten it to inline with the mouth sort of) and make the angle back to the ear less severe, it will solve most of the stewie face problems.
try bring the eyes in and squash the eyes a bit aswell, it looks right on the flat, you're using real world proportions, not tori squashing proportions, thats why people started working on 1024x1024.

stretching the sides of his fringe might be a good idea too, it looks a bit too much like a scruffy school boy haircut atm, you want killua to be a bit more delinquent like.

i like the simple version the best, the shading attempts on the others looked terribad.
if you can figure out a way to differentiate your face shapes from dengues and bring in some really subtle depth to the face, you could have found your niche in the texturing scene, the way you did the eyes and hair is >>

its funny coming from you, who used to like wrapping long thin moster eyes halfway around the head :P

BenD, it is okay and not stewie, the only mistake is the chin that must end lower, the neck appearing in the sides of the jaw a small problem compared to his achievements with this head.

Thanks for the great critique, but I think I'm rather finished with this head,
but I will be using your helpful tips on any other pieces I decide to work on.