The skull is way too shallow in the side view. If you are working in zbrush make the interface transparent and place an image of a skull in side view under your sculpt. Nice work.
Looking good ! The eyes are possibly too wide and the skull is still too shallow on the side view, even if it's better now. Also you should start some asymmetry on the face using a layer; especially on the lower lip: one side is much thinner than the other, it will enhance the likeness. Keep up !