Nice head, really nice head to tell u the truth, there's any things that makes me like this head, and make it kinda unique in my opinion, first of all the simplicity in that is really well executed, i like the mix of realistic style with manga style, but the thing that really got my atention was the fact that this head reminds me of a sketch made with pencil, and that's what really makes this head unique in my point of view, mainly cuz u executed that with perfection, i think the only thing u could do, i actually don't know if it is a good opition, but i think adding some little highlight to his hair would be nice.

And pls, create ur artstation.