Idea: Would it be useful to add 'patterns' as another layer in the heatmaps, or is it unnecessary and complex? Personally, I've never needed them since we can already use text, color, background color, and outlines.
https://www.rdocumentation.org/packages/gridpattern/versions/1.3.1/topics/grid.pattern https://coolbutuseless.github.io/package/ggpattern/articles/patterns-points.html https://coolbutuseless.github.io/package/ggpattern/articles/geom-gallery-array.html#geom-bar-pattern-