Alas, we are closing in on the final weeks of this summer's Mostly Mozart Festival. Fear not, though, Classicalites. The home stretch of Mostly Mozarts past there at Lincoln Center have always been filled with must-hear performers in don't-miss programming, and this 2015 iteration is hardly going out with a whimper. Case in point: the much-awaited American stage premiere of British composer George Benjamin's love-hate opera, 'Written on Skin.' Starring Barbara Hannigan and Christopher Purves in the viscerally erotic roles they, themselves, originated, outgoing New York Philharmonic music director Alan Gilbert leads the Mahler Chamber Orchestra in what's fast becoming the most revered English-language opera in some two decades.