As a company that is trying to go paperless, when the invoice is created in 365 if it created a folder with the invoice in, rather than just the invoice as a file, then we could add any relating documents or comms such as quotations and customer orders into the folder instead of still having to print everything for our accountants.
Another quick one would be the ability to change how the name is added when the file is created. At the moment it is SalesInvoice #### it drives all of us mad that there is no space between Sales and Invoice.