I’m afraid we don’t have any plans to make the file naming customizable. There is another thread about it and the reasons (mainly technical) have not changed. Tweak the article naming in Google Drive
We are not against it and would love to have the feature but given the long list of other feature requests and technical challenges it won’t happen in the near future.
Also, you can’t change the file names manually. They will be changed back next time Paperpile syncs. The Paperpile folder should be seen as a data store for Paperpile. You can’t damage anything when you change files but it’s not a full two-way-sync where all changes go in both directions.