Take the following image, for example:
I'd like to represent the lineart not as a black-filled, closed object, but as a network of Bézier curves connected at odd places, with various and varying stroke widths between them. When I manipulate a curve that has other curves connected to it on its arc (not just at its endpoints), the other curves should adjust to stay connected to the one I'm manipulating.
Additionally, I'd like to represent the coloring as a set of "fill points" that, when rendering the image, propagate their color out in a wavefront until they encounter a Bézier curve - just like a flood fill tool in raster programs, just not prerendered.
Is there a vector graphics format (and editor) with which this can be done? I've only had casual access to Inkscape/SVG, but the graphics primitives it offers are indeed too primitive.