I have much hope that this discussion will be fruitful.
@MWilliams24 and @chriscas -
One of the questions you have both discussed is who, if anyone, should be able to delete an assignment. Both of you are posting from the point of a view of a Canvas school administrator. I would like to share some of my thoughts as a tenured community college professor.
At my college, we have a classified staff member who serves as our Canvas administrator. His role is to address technical issues. To involve him in questions related to a student's academic performance would be inappropriate. I don't need, and shouldn't need, the college's Canvas administrator's "approval" to make decisions on how I teach my courses or deal with student-related issues.
I'm also a former vice chair of the largest department in my college. In that role, I rarely got involved in the day-to-day classroom interactions between my fellow faculty members and their students, and only did so when a student filed a complaint or an instructor requested my assistance. Why should teaching online be any different than in a traditional face-to-face class?
My Canvas courses contain numerous graded assignments. When anyone hears the word "assignment," they often picture summative assignments, such as term papers, which carry a great deal of importance in determining the student's final grade. The reality is that many instructors, including myself, have created dozens and dozens of small, formative assignments.
If a student makes a mistake and submits Monday's homework instead of Tuesday's homework for an assignment, why shouldn't I be able to delete the submission? Are you suggesting that I should have to jump through hoops and get the approval of my college's Canvas administrator, or my department chair, or maybe my dean? Why? Please trust your teachers and your professors to make wise decisions. Don't take our authority and control from us.
And, Canvas already gives instructors the ability to edit and delete graded student work in discussions. If the student posts a reply to Monday's discussion in the Tuesday discussion thread, I can fix it. It's easy to do, and I don't need anyone's approval. Of course, if a student's participation in the discussion is problematic, I would take a screenshot of it as a record. In this case (graded discussions), I already have authority and control.
Because some assignments are, in fact, important summative assignments, the best solution would be the "soft delete." A retrievable copy of the student's original submission with the time stamp (etc.) should be saved.
Finally, I would not give students the ability to edit or delete their assignments once they have been submitted. Because I grade my students' discussions, I have turned off this option for them as well.