Not sure if this is beyond the scope of this extension, but would it be possible to detect when someone is attempting to upload an identical file from another Wikimedia project (like English Wikipedia) directly to Commons and change that action into a FileImport automagically? This would help keep revision histories intact, and stop editors who may be deliberately trying to "take credit" for work they didn't do from doing so (bonus points if it detects an attempt to upload a non-current version of an identical file from another project).
Topic on Help talk:Extension:FileImporter
I think this is technically possible. It can probably reuse the technology we can see at the bottom of Commons file description pages where usages in other wikis are listed. What makes it especially complicated is that there are so many ways to upload files. Some UX work is needed as well to let the user know what's going on. The team at Wikimedia Deutschland currently doesn't have the resources to work on this. But it might be wort a feature-request ticket on Phabricator.
Done, as phab:T312875.