I’m a firm believer in traveling carry-on only, as much as possible—and while it’s essential to choose the right suitcase, another key element of my strategy is to select a lightweight, versatile bag for touring during the day, as well as a transitional clutch and other easy-to-pack accessories for evenings. As I’m preparing for autumn adventures in culture capitals like Antwerp, Florence, Paris and Tel Aviv—and busy days in New York City—these are the kinds of bags I won’t travel without. See a...