Faces are the hardest to do in 3D, eyes are the mirrors of the soul and all that, but maybe we don’t need eyes at all? Try talking to someone with your eyes closed, it’s very difficult.
I subjected friend and actress Wieke Van Rosmalen to a structured light scanner that is really not suitable for this task to see where we get with some very high resolution but glitchy results.

Glichy scan of Wieke Van Rosmalen