Potlatch2 without OSM???

I need a map editor web-app. Potlatch2 seems to be the most comprehensive. I’ve looked into OpenLayers vector editing. Its pretty limiting.

Is it possible to feed Potlatch2 specific data… Or even have it speak to a non-OSM database.
If an OSM database is necessary can I limit the data a user can edit,… lock or only show parts of the database.

I have no need to render the data. So, a custom OSM server would be overkill. I would like to avoid setting one up, or at least in its entirety. The data will be a vector layer with an OSM/Bing/Google base map.

If this wont work are there any other web map editors that someone is willing to recommend.