The dataset might not be ideal, because several points have shared offsets, causing random coloring and jitter when resizing.

fixed below! danke

Have you considered turning this into a Plot mark, e.g. as an alternative to the dot mark for densely packed points?

the raster mark already does this (more or less), but it would need a custom interpolator to limit the radius. https://github.com/observablehq/plot/issues/1431

While the shifting of the points towards the center is undoubtedly visually pleasing, I'd like to suggest setting the margin to the max selectable radius so that the effects of changing the radius can be observed more easily.

done, thanks!