Dotted with turquoise lounge chairs, ruffled umbrellas, and white-sand beaches, this newly reconceived and rebranded hotel is now part of the Waldorf-Astoria collection and looks as if it was carefully replicated from a retro-chic postcard. An annex of the larger Mediterranean-style Boca Raton Resort & Club (but set on the downy sands rather than the Intracoastal Waterway), the casually elegant...