I think OpenStreeMap could benefit immensely from investing a bit in making self-hosted versions more approachable and on more platforms, especially now that vector-tiles are becoming increasingly used.

I would love to quickly install a small subset of the planet (say my home city or country) on a cheap webhost with a simple LAMP stack. Then have the map just use that server whenever it fits within the bounds of my subsets and then possibly fallback to other or the public servers if requesting data from outside.

Routing also seems like something that could technically be done (albeit less efficient than dedicated C++ implementations) on cheap servers but I guess it would require more work.

Rolling out map updates for all these self-hosted instances is a bit of another problem but I'm sure it can be done.