No tips on shading but on how to draw sided faces:
1.The forehead it's not usually that prominent.
2.Tho the eyes are at good height, they're usually closer to the nasal plane.
3.On the second drawing the chin's curve is too pronounced, try to be more subtle.
This pic might actually help you:
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Also..>.> Could you rotate your pictures before uploading them? Is kinda annoying to have to turn the neck to see them right...
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After the Cnc, I must say that eye on the top looks great