we brainstorm how we might provide server-side support for medium sized databases with some analogies with the "commons" managed by the new Image plugin.
An admin can install the plugin with Plugmatic. The plugin's about pages will describe how any user can create, update and discard shared database files. A more-about page will describe service operator's administrative responsibilities like backup and restore.
Any hosted site owner can add the SQLite plugin to a page which will provide access to a shared database file named by the page's slug. The client-side will offer buttons to "create", "backup", "download" and "destroy". Markup will describe access and retention policy.
Once installed, enabled server-side plugins can create and manage database files consistent with their purposes.