In my observation a single income setup is some kind of local optimum. I've never met a full time homemaker who thinks she's getting a raw deal. It is a real job that requires an exceptional level of responsibility, creativity, and effort, but it's one that is extremely financially and emotionally rewarding. When I ask they all say, essentially, "We didn't want work just to hire someone else to raise our children for us." That said, part time hired help is very affordable in the USA too. You can get a fully qualified part time babysitter who is also willing to do light housework for about $15 an hour in California. I imagine in other states it's even more affordable.

When you look at the market value of the labor the homemaker does for the household, and consider that it accrues tax-free, the financial benefits are considerable. And there are also substantial tax benefits to married filing jointly when one spouse has no taxable income. For the arrangement to be successful though, the "working" spouse needs to fully recognize the value provided to the household and make sure it's well compensated, both emotionally and financially. If you can do that, it works extremely well.