Nice subject.
The flesh color reminds me of fresh tuna. I wonder if a more vivid red would feel less uncanny, even if this color is plausible for dried out muscles.
I agree about the painted feel. The heavily painted lighting/AO in the diffuse map spoils the realism. Although a new diffuse would be a hard work, maybe the other attributes could easily improve the render with little mapping manipulation. All materials look the same: flesh, cartilage, bone, ligaments and fat.
Now you made me remember 2011 Heidi Klum's Halloween costume:

GTX 1080 8gb, GTX 970 4gb, I5 4590, Z97-E, 32gb RAM, Win 10 64bits, Octane for Maya