I would love to see Canvas add a button that makes it easy for students to 'Like' assignments. As an instructor I am always curious about how students feel about their learning. In the classroom it was easy to assess if students enjoyed what they were learning and how they were learning it, but this is much more challenging in the sterile online learning environment. How about making it easy for students to respond to the assignments they are doing and providing instructors with a report that shows how many likes assignments receive to make their courses better.
As a secondary feature, it would be nice if students could also respond to a quick prompt if the assignment was useful for their LEARNING. This is something we always strive for in education: meta-cognition. I would love to know, not only if student had fun with an assignment, but if they learned from doing that assignment.
So maybe a thumbs-up (like) button and a learning (light bulb?) button on each assignment. I'm sure teachers could find creative ways (extra credit) to encourage students to use this feature.