I confess that I don't have much curated data to share but have often thought about this, even from a safety perspective. I was in a serious storm once that tore my tent apart and I spent 48 hours in serious cold with little shelter - I later found out that there was a very large overhanging rock that provides great shelter less than 1km from where I had been. It's only a marginal feature so not worth including on maps but a potential lifesaver in certain circumstances.
A quick scan of your kind of site prior to heading into a certain catchment could result in less incidents and more people safely experiencing the outdoors and thus becoming more informed voters about our resources.