I see what you're saying there Waldron. Strangely, while I'm pretty well grounded in the math, I have a lot of trouble visualizing the results.

I'm curious is there any way to get a mask of basin areas from the Fill Basins filter? Failing that, and perhaps more generally useful, could you have a 'Select Flat' option. That is a selector that scans a window around each pixel(say 3x3) and selects that pixel if and only if all points within that window are within a given variation(epsilon?) of each other. Then you could noise up the supernaturally flat basins while leaving the yummy ridginess of the mountains pristine.

I wasn't initially sold on the terracing produced by the Remap Altitudes, but I like how the Precipiton mostly beats that down. It also erases a lot of the streambeds. Another thin Incise Flow at that point might be nice. (?)

Anyway this deserves a rep.