Possibilities of Value Grouping

Hey everyone, here's a portrait I recently finished as a part of a personal project! I'm not entirely happy with it, especially compared to the 2 previous ones, but I want to use it as an example of value grouping. 

My goal with this image was to have a very clear graphic read of the beard and clothing, while keeping the skin value range very narrow. What this means, in other words, is that the contrast between the light and shadow in these areas is very low - being virtually nonexistent in the beard, since it's just a flat color, and low in the skin, since the light and shadow are fairly close on the value scale. 

Now I'd like to show you a couple different way I could have gone about this image, to illustrate better the kind of freedom you have in making decisions concerning value ranges:

Here are a couple very different visual solutions I could have gone with, achieving vastly different visual reads, while still maintaining the actual material/objective read of what is shown in the image, which is a black beard and skin. 

Here's an image by Thomas Blackshear that shows a very similar sort of value grouping (except done much more masterfully than what I had managed in my painting):

Here are also some process shots of my painting:

The process is much the same as the previous portrait I posted, but I still thought it might be interesting to see it, as well as this discarded version:

You can probably see why I gave up on it, I was just not getting the face right. For the version that I actually wound up finishing, I had a much more concrete reference:

And here's the full ref board:

Hopefully this elucidates some aspects of using value as a visual tool that you might not have been aware of previously, and feel free to let me know if you have any questions regarding this or any other topic.

God bless,

Ognjen