Currently, the workflow to add a rubric to a graded discussion is different from an assignment workflow and from a discussion workflow - as described at https://community.canvaslms.com/t5/Instructor-Guide/How-do-I-add-a-rubric-to-a-graded-discussion/ta-.... This makes it non-intuitive and hard to find for instructors, unless they trawl the Canvas community forums (most don't).
In discussion Options, when I check the Graded box to indicate the discussion is graded, allow me to assign a rubric right there, from the options. This would make the process more intuitive and user-friendly, bringing it somewhat in line with assignments.
