I guess if your underlying data is not uniform, a uniform color map isn't going to do great? Say, if you have a bimodal underlying distribution and you're inte

I guess if your underlying data is not uniform, a uniform color map isn't going to do great? Say, if you have a bimodal underlying distribution and you're interested in coloring according to quantiles, you want to have a similarly bimodally distributed color map. The easiest way to achieve this is to compute the quantiles for your data set, and color by that (rather than height).