Hi Niels,
I was thinking in how it would work for quick storyboard panels and maybe use animation paper for storyboarding short scenes. With one brush set in “paint behind” mode you can draw, first the line, then a quick shadow and then fill it, all in one layer and with one tool, only changing colors. I thought this would give a fairly decent finished look for storyboarding and it would make it super easy and quick to do. Having it in one layer keep things more manageable when you have more than one character in the scene.
I didn´t know painting features were coming, you keep doing this software very very good!