I think there are many issues currently with course analytics, though the idea of it is great. Your suggestion of being able to filter by section is a step in the right direction. The ability to filter in general should really be focused on. It would be nice to filter grades by assignment category, for one. I still for the life of me don't understand what Participation refers to. It might help if I could click on that count next to a student's name to see what they "participated in". At least you can filter by student. Anyway, rant over. Good idea!