I'm a bit out of breath, but def not out of projects :) Gonna keep doing this until I get an answer from NLNet.
In 2010 Microsoft granted to OSM permission to trace Bing imagery. It was the only detailed imagery layer we had in Russia, so that enabled making a validator that found illegal imagery usage (google / yandex):
Basically it watched where people uploaded buildings and checked for available Bing imagery.
In 2014 we got Mapbox layer, and I turned this off.
There are different kinds of imports. Safest are those done by hand, but also the dirtiest, in my opinion: it's easy to miss or to get lazy and just press upload.
For towns and villages, the best source we had was GNS, an american database of toponyms. I converted it to OSM format and wrote a short manual on copying it onto the map:
http://gns.osmz.ru/
Interesting that while box=yes parameter doesn't work on osm.org nowadays, parameters minlat, maxlat etc still do.