That's fair... we chose to drop the shading at that zoom, but we could be wrong. I think some people prefer a cleaner read when zoomed in so far (especially for field use), and shading also makes the tiles larger/slower to download.

Gaia GPS does have a separate raster hill-shading layer from ESRI you could layer on top, and we've been considering making our own (we already have an elevation data pipeline and create contour lines, so hill-shading isn't a huge step). Maybe that would have a special UX where you could choose to include it or not in your downloads.

I dig your map style!