Personally, it's a matter of taste. There's no law that says you have to rush out and buy 7" heels to totter around in. In the end it's how comfortable you feel in the footwear you choose. I have a couple pair of flats that I like to wear if I'm going to be running around all day, I have heels in heights ranging from 2" to 4". The 4" I usually wear for my fetish photo shoots. But my 2" heels, I can walk in them all day and feel just fine. But no matter what heel height, my feet are going to be sore if I'm on my feet all day regardless. My feet can get sore even when I'm in guy mode wearing sneakers, LOL!
-Audrey