Many years ago I would make a value study drawing in graphite and then water color over it. What a surprise to find out I was doing a Titian technique (of sorts - his were in oil) called grisaille, which is simply a painting done in shades of gray from black to white. The under painting, which was first done in burnt umber, then in grisaille, and then many glazes of transparent oil pigments. I gotta tell you, Titian worked a whole lot faster then I did. It took me a month of classes, and sessions between, to finish this little 16 x 20 inch canvas. But then, I didn't have a cadre of apprentices, either which makes for a handy excuse for being so slow! (I don't have a wife, either.)
As to the final solution, I have some things in mind, and when they are in place you will see an altered image.
But, next I will post the woodcut for the exchange.