Currently there is a tree that displays the courses that are pre-requisites for a chosen course, but I think it would also be quite useful to have a tree in the opposite direction. So after choosing a course, you can see what other courses this chosen course unlocks (what it's a pre-requisite for). I think that this would be quite useful, especially when picking electives. Also it shouldn't be too hard to implement :)

P.S I really like this website. Well done! Soon it might be UofT's equivalent to UWflow :)