Some test colors applied to this, did some more shading. The project is advancing OK so far I think.
However, I'm facing from frustration recently. Firstly, I don't believe there is a polygonal marquee tool in GIMP, which means I've got to make all my selections with paths and then create a selection from the path. It does work, but it seems slower than my usual methods.
Secondly, and more of a problem, I'm getting some artifacts in my large feather brushes that I use for shading. This shows most evidently on a solid background, but as I layer in more it seems to blend in. I'm testing different flow, rate, and opacity settings to try to minimize this.
EDIT: I'll also mention here that this is being painted at 3000x1144 px. And I'll add a 1:1 image that shows the artifacts I'm seeing:
