Splats are smallest at the point in the image where I want the most detail shown, and each splat is shaded. The shading is based on a light direction which is currently stuck to that detail focal point. Note the direction of the highlights and shadows:
I want to be able to set these points separately. The math is trivial (after having done bunch of other nontrivial math) but I don't have a good UI for it yet. So for this example image, I just hard-coded the light direction to be coming from the upper left corner:
It definitely changes the feel of the image. It will be more subtle in real images (I crank up parameters to make my point obvious in these examples) but I'm excited about it.