Too much of a good thing?

On the one hand, a vacation is very much needed. A break from the routine of classes stimulates our minds by changing pace. There is more time to study for exams that are coming up, catch up on work we have left to do, or just ignore school and work altogether and catch up on sleep, hang out, relax be with friends and get away from campus food. Finally, there's time to see all those movies that are coming out and just go and do what we want to do. It's a slow-down, to step back, take a deep breath and prepare to get ready for the next round.

On the other hand, just what is the right length of time? Too much time and a different routine emerges, sleep in, get up, eat lunch do nothing for a while and go back to sleep. And while the vacation seems like a break from moving too fast, really, we move to slowly. And then of course, because we have a break from our routines, we fill it up with things we normally aren't able to fit in, like doctor's appointments which of course need follow ups that we don't have time for because the break doesn't accommodate them. All the work we plan to catch up on to be ready when the pace of life picks up again never really gets done because there's always more time tomorrow to do work and it's vacation, lets sit and rest.

How much of a good thing is too much? At what point does the vacation stop being a good thing and become boredom on the calendar? Does this apply to all good things? If so, what about the good life? How good should the good life be?