So far as I know, MyPaint is only for digital painting.
My approach to art might be called multi-pronged. There are many ways to mix computer with human capabilities, most of which probably haven't been thought of and may never be thought of. Personally I favor the two extremes:
a) almost totally manual, using the computer only to simulate the properties of traditional tools and media (and possibly some extensions thereof), and
b) almost totally automatic, letting the computer generate the styles, the methods, and even the software that generates the styles and methods.
for me personally, the most fun and artistic, hands on work (so to speak) aspect of my psy animations is the 3d modeling.
the actually animating is a mix of procedural techniques and manual keyframing, although i am leaning how to better tweak the inbetween frame data, mainly to get the movement of my objects more fluid and less stiff looking.
unfortunately, there is also a lot of behind the scenes, very laborious, configuring of blender's interface. and in a project as complex as mine, a lot of managing of the folder structure and naming conventions, other wise i loose track of the hundreds of different components, and tens of thousands of individual rendered frames of animation, that i have to keep stored on my pc, until i have done the post rendering effects.
i would love to just be able to get across my artistic vision for this work, without all the behind the scenes crap, but i think we're a few years off, at least, before the tools are that advanced.