this is great. With the amount of time that you probably spent on this, it is very detailed, but have you looked in to sub-surface shading? I'm not sure if you had used it but adding or increasing the level of subsurface shading could help mimic skin because light passes through skin. Also the the amount of specularity in the face makes it seem more like silly putty or chocolate pudding rather than skin. Just lowering the reflectiveness a little will make it feel more realistic. you could also work on making the eyes more believable by adding folding of skin above them rather than pulling and stretching them up. putting major detail in the eyes helps to increase realism. It's great the way it is, but subsurface shading has been out for a while and most people don't make use of it. just because he is evil doesn't mean he has different skin than you. keep doing what you are doing and good luck.