Oddly, I have two sub directories in my Google Drive under Submissions that are named as the FormID (from XLSForm) where the media files are stored for the respective submissions (filenames are the full path) - I didn't knowingly create or specify these, so I wonder how / why they are there. For other forms they are in the main Submissions directory - as you describe.
Personally, I think your suggestion is good, retains a logical structure and is consistent with other ODK tools. Of course, with your suggestion of folder structure and naming convention, it could open the way to extending Briefcase to pull from Google Drive, or downloading and pointing to a 'Collect Directory', if you were to insert the instance xml in that folder as well... Just thinking ahead!
One thing I hadn't appreciated until about 2 minutes ago, which might cause me some problems if I want to download the media files related to form submissions, is that I think the media files are stored on the Drive of the person that uploads them, not on the same Drive account as the upload spreadsheet? I didn't see this documented anywhere, but that appears to be the case. Just wondering about that and whether it is feasible to manage things in a way that allows the survey data to be 'hosted' in a single account - also relevant to my previous point. What happens if an enumerator has a clear-out of their drive, finds a folder full of images and thinks that they can be deleted...
So I was thinking that in parallel to specifying the submission target spreadsheet, another would be the target folder for media? Getting a bit more complicated...
But it potentially causes trouble with permissions for different folders across Drive - that might be a whole new can of worms? Obvious privacy problems if the data is openly available, but it could be an administrative headache to manage the spreadsheet and submission folder(s) permissions separately?
Thanks for dedicating time to Google Sheets issues. Much appreciated.
