The big toe, second and third toes are usually visible in peep toe shoes. Just saying. In any event, these shoes are flattering for many different shapes of feet, which is probably what makes them so popular.
I like a peep toe slingback, myself, which keeps me from getting blistered heels. I prefer a 2-inch heel height at most, since I have no interest in breaking an ankle in a platform or stiletto shoe.
Women should make sure their shoes are wide enough, since compressing the toes can cause nasty conditions like bunions and hammer toe.