A progress bar on the status of grades uploading would be very useful. Many instructors teach large classes that have many assignments, and some upload spreadsheets for grades. In some instances, some of the uploaded grades would be brand new, while some would be replacing existing grades. The only way to see if the grades are done uploading is to refresh the Gradebook and manually check if the grades are old or new, so a progress bar that indicates how far along the Gradebook is in being updated would be very useful.
Additionally, this would be helpful when there are multiple TA's who do their own grading, so that the instructor would know if a TA was uploading a spreadsheet, which would allow the instructor to know to delay uploading their own spreadsheet to avoid any complications.