This might be the start of a good approach, but I think it would largely reward popular teachers and easy classes. Back in university I would not have trusted myself to decide which were the necessary classes. With family, stress, work, etc. it would be too tempting to take the easy road. Maybe some combination of students and teachers...
I think rewarding popular teachers would be a feature rather than a bug. As for the too-easy problem, well, if you had to take a certification exam (like, for example, the bar exam) then you would have to choose the courses you thought would most likely help you pass.
My larger point was that the current educational system has stagnated and seems to be frozen in the late 19th century. It is highly--even actively--resistant to change. It is very expensive for the results it delivers. Whatever the right answer is (if there is one) requires thinking about the root causes of the problems and possibly fundamental change. Unfortunately, with topics like these people seem to want a different result without changing the underlying system that produces that result.
