If it were me, I would not count the assumption that you and your wife will start a successful home based business into your decision. I’d assume that you will be the only one working, or that your wife will have to take what job she can get in a town of less than 100,000 in the middle of the midwest. Then you can sprinkle in whatever optimism you want.
It’s a tough decision, but personally for me, I’d go to school.