Usually with sculpting tools you may create the foundations for a head mesh, with the right polygon flow, then sculpt the extra details, which would be converted into a normal map. The reason being, the head mesh would provide more structure and would look better in a game situation as well as the render. Though people do have the talent to make a decent looking head from a sphere in Mudbox and Zbrush, but not the best route I think for a game modeller.
Or at least from the way I look at it, but if you can make it look good enough with the normal mapped lower poly version, then I'm sure it won't matter. But I think the better route is one to aim for. (Just as a bit of critique)
Anyway, bergice, it's looking good, I am glad to see some Leadwerks games getting out there - have you got some gameplay elements being built up? It'd be cool to see what elements you're introducing in action.