please read the art board rules, (wip) isnt a valid tag anymore, changed it for you this time.
angle the eyes slightly, flat eyes dont usually look great, unless youre looking for that specific look.
circles will map in an oval shape if you dont squash them 50% horizontally, there should be something in the tutorial board that will explain it better. otherwise have a look at some other textures to see what i mean.
i wouldnt attempt shading with that that style, keep using flat colour, will turn out nicely. the current face style looks like a good african art style, keep at it and make it your own