Here's another experiment. I made another brush and customized it's properties more to my taste. I was able to figure out how to do a basic grisaille underpainting/sketch, set them to multiply and then added the color and highlights in separate layers thanks to some online tutorials that reminded me this technique existed. Actually, this is a very common technique in traditional painting and I've used it before. I don't know what it is about the digital medium, but it has this ability to make you forget everything you learned when you were working traditionally when that's not really the goal. I think half my battle will be just understanding how to use the digital tools exactly the way I used my traditional brushes and paint. I just have buttons and settings to set correctly before I get the right effect.
The background was also fun. I really didn't have much of a plan for it except that I wanted it to convey the light source's direction.