This maybe a duplicate. May need training in effective tracker searches.
It is important to me to vet each question. I thought a comment field could be a multipe purpose way fulfilling many needs. It is less important for me to know who authored the question and when. We do not need the students to comment or rate the question. These things could be hidden under an "advanced field" button to keep the clutter down. They should be export/import and backup enabled. When Moodle allows printing of questions in a report, these fields should be printed.
A searching filter in the question bank, would have to take into account context of course and role. The admin role could find all a particular teachers questions in a category. The teacher would only be able to see all their questions in the site, or in courses they taught.. Teachers should also be able to search/see other teacher's questions in courses which are taught by both.
I am sure this is not easy. Just a comment field attached to a question would be good.
Sorry to ramble, feel free to delete this and send me the links to other tracker items that I can follow.