A podiatrist who surgically repaired a bunion ~20 years ago told me I had "functionally flat feet." I walk fine, no pain, etc. When I look at this diagram I have a slim print like I always have so I set aside that information as possibly incorrect. (He wanted to sell me some custom orthotics.)

That said, since the surgery I wear flat shoes, with only a couple of pair that have a 1" heel for special occasions. And a few years ago I found an orthopedic brand called Propét that has a lot of attractive walking shoe styles. Much less expensive than the ones Sandra linked to and these are incredibly comfortable.