What do you guys think about this? How can I improve it? What should I do with the top part of his head, it looks kind of bland to me?
I’m not a professional at building or GUIs, but you could try adding a few hairs or a hat for variation if your feeling that the head is a bit empty.
I think you should add some messy strands of thin hair on its head.
A few scars on the face maybe?
What is the purpose of it? It might give a better understanding on how to improve if given context.
I would focus on adding basic shading for now - the mouth slowly becomes darker to create depth but you haven’t done that with the skin or brains making it look flat.
Also you could maybe add stitch marks like on various depictions of Frankenstein’s monster to the spot of the head which you say looks bland.
7/10 give him some hair but except that everything is good. I
I would give the zombie some cut marks near the eye or mouth and like the other people mentioned, some hair.