All in all a fantastic start!

Everything is at its place.

You should add another view ("Dreiviertelansicht") which shows both, side and front view, in a way that you see the cheek behind the nose. This view shows more of the general impression of the head than the other views! Then you can see wether an eye brow would add something special, or wether it needs only painted in the skin.

To achieve a "beautyful" head - as often used for main characters - you should move up the mouth and nose a bit. And scale it taller. But you can easely do such modifications later. Especially, when you like to use it as prototype for different characters.