I'm not sure of the magnitude of this work but I believe plone.importexport(Gsoc'17 idea) can be projected again with ideas/tasks -
- Upload from another site. Enter url and do auth and stream content between sites, which would cut down the extra burden of handling and tracking of files.
- Enhancing the advance tab, UI and the existing Upload pattern (which currently only allows multifile upload).
- Resolving Open issues which require a few sprints.