... the vision is in Clear Canvas, and the power is in ease of workflow ...
... a blank canvas is a terrifying thing ... so we embrace clutter, more tools, more surfaces, more colors all at once and right at hand, we are anxious to fill up the space before we've laid down a single brushstroke ...
... your design invokes the principle of less is more, and is a giant step toward the seamless integration of work and vision, with greater emphasis on vision (deviantart boasts 230 million images, so execution isn't a problem) ...
... a paradox of digital art is that it enables faster execution of an idea but threatens to diminish our feel for things in the world ... revisioned in art ...
edit: forgot to mention the chalk wash you've asked about ... so here's a detail from an image I posted earlier this year on this forum ... the idea was to create a single-stroke classical Chinese landscape mountain that moves in gradation from deep black (ink) to a delicate wash ... after much experimentation (read: frustration), I finally hit upon a thin 1% chalk underdrawing, which I then washed over to produce this effect ... so the advantages of a chalk underdrawing for what I'm trying to do are twofold, thicker body paint that can be washed out into natural-looking gradations, and less work to achieve what I want ... admittedly, as I've said, this technique is inefficient and limited to what I'm trying to do, I only point to it because you asked :-)