For my office job I had to deal with dropbox and public uploads aspects.
I just find Requests system : https://www.dropbox.com/requests and I have to say that it is very intersting. This kind of usage would be helpful for nextcloud usages :
- Move to specific folder (ie : Documents/Projects/Consumer1)
- Create a Request form
- Appear a msg box where we write a short description about wished files
- Next and then specify email address
Then, a mail with a huge and visible button is send to user which we want file from. There, this user just have to open the link and click Browse to send file.
Actually, public upload is very very helpful but a bit boring to use for final user. (not very interactive interface)