This week in SundayArts News: Picasso at the Met thru 8/1, Keys to the Future at Le Poisson Rouge 5/25-27, American Ballet Theater 70th anniversary season thru 7/10, Emily Dickinson’s Garden at New York Botanical Garden thru 6/13, La Cage Aux Folles at Longacre Theatre, Palladio and His Legacy: A Transatlantic Journey thru 8/1 at the Morgan.