Hey Bill, This is a very nice drawing, your control over your values is pretty good. If you want to push yourself a little, start thinking about the structure under the eye and it's surroundings. I did a very crude paint-over of your eye to kind of show you what I mean. I didn't use any reference so it's not perfect. I darkened areas that would be in shadow because of the brow and the socket it is sitting in. Sometimes the reference is so Photoshoped and processed that everything looks kind of slick and flat. Also, pay attention to the pupil, it's kind of counter intuitive, but the pupil is lighter across from the highlight because its actually a bowl shape. Anyway, I hope this helps :)