After more than a year of struggling to re-create the feeling of my original head concept art, I finally got something I am happy with using a combination of Blender and Inventor.

I did the wireframe in Blender starting from the modeling clay sculpt I did in my last update, and adjusting slightly for the concept art and various references from different angles. Then I made it into a solid in Inventor.

I just need a little more problem-solving to connect all facial parts to servos, and of course connecting the head to the body with rotate/tilt system used in animatronics.