Allow larger file sizes than 10 MB
The current limit of 10MB seems fairly small in today's age. Previous explanations that the document will be emailed and/or opened on mobile devices that can't handle large files is pretty much moot now, because both can typically handle larger files (say 25-40 MB).
This was a very frustrating error to run into when uploading a client proposal with pictures.
I tried to send files to our printers, to no avail. I kept getting an "error while uploading" message, now I know it's because Adobe lives in the area of "not bigger than 10". Unbelievable. 10GB should be the limit, if any at all.