When giving an assignment with an attached Google Doc, teachers have to manually unsubmit the assignment every time that we would like a student to redo the work. This is not the case when a Google Doc is not attached; students can resubmit anything that they create or upload.
Also, once an assignment is resubmitted, it needs to be easily located through the dropdown submission grading tab, "Resubmitted". Unless a student personally informs you or scrolling endlessly through the notifications, I'm unable to find the assignment to grade.
Finally, the ability to choose if the assignment is able to be resubmitted for a better grade should be a choice button when creating the assignment, as it is in the test/quiz settings.