Yes, anatomical inaccuracy is the first thing that stands out. Once you get the sculpt down, try working on color zones for both the base color and the sub surface scattering color.
You probably box modeled this in Max right? Really the way to go is sculpting. You dont need zBrush for this (although it helps). Alot of 3d apps have the capability these days. One example is the open source software Blender3D. Place a human scull model under your sculpt to check on structure as you go. Make alot of studies!
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https://alvalyn.com/using-color-zones-portraits/
The lighting could use more pop, it's very dark and grey and flat right now Last the render has a lot of noise in it. Try increasing the samples.
Have fun.