How would you feel about integrating https://mapcomplete.org/bookcases.html? (which I make) as means of contribution?

This one sends data straight to OSM. I don't have my own database to "moderate", pictures are saved into a Panoramax-instance.

As users authenticate by logging in with OSM, the boring, risky legal stuff is handled by OpenStreetMap. Uploading images has a small print that says that their images will be reshared under CC-BY-SA.

The part where I suck is in creating a nice, polished website with extra pages, SEO, ...