I like the 4 day week, but that is because I have kids who are teenagers. Giving them some extra time each night with their parents is not important to them. But having an extra day to do something big, explore a new place, go to new museums, take small road trips, go camping, etc. - that makes a difference in their life.
When they get older and go off on their own, though, I would agree with you - a short daily working routine sounds good for me personally.
I guess 4 day school days wouldn't be a bad idea either... of course the other day should be filled with something productive, which may or may not include "schooling" (learning) or "working" (as in creating, not paid/unpaid labor) or other form of activity.
The college I graduated from for the most part didn't offer classes on Friday and I can attest that it was wonderful as a student. It meant that I could get homework done and/or work a side job on Friday and still have a proper weekend to re-coup for the next week.
When they get older and go off on their own, though, I would agree with you - a short daily working routine sounds good for me personally.