A question on a related topic, then: given that hats are dead, how can a person appear reasonably good if they want to wear a hat for comfort/practical reasons?

Clearly one of the big no-nos is mixing formal and casual. Fedora wearers without a suit, also the weird college-student fad of wearing a waistcoat ("vest") with casual clothing, much ridiculed. But on the other hand, wooly hats and baseball caps are more casual than a lot of general leisure and business clothing. We have the flat cap, but here in England that seems like an affectation unless you're from particular places where it's traditional. What alternatives are there?