Dear Frank
This is coming along very nicely indeed. I really like the well balanced flesh tones and I see you made progress on his coat. It may help but have a look at different versions of this painting if you look it up on Google images. I don't want to cloud the issue but seeing slightly different pictures may help it turn out to be a better flat. This is because it may help you to see how the same image can appear when slightly lighter or darker, etc. This way you can choose what you think would work best.
I hope I haven't over complicated things. I'll shut up now, as you seem to be doing a good enough job without me. Best of luck with it!
Anthony