A seven-story atrium will create a dramatic punctuation at the top of the Legacy Hotel & Residences at downtown’s Miami Worldcenter. The design, by architect Kobi Karp, creates an oasis in the sky with a cantilevered Singapore-style pool, rooftop bar and panoramic views. The Legacy project, 942 NE First Ave., will have a 274-unit residential tower atop a 256-room hotel. Daily rental of units will be allowed. The developer is Royal Palm Cos., led by CEO Daniel Kodsi. Sales are being handled by One World Properties.