This summer, the Mostly Mozart Festival will reconfigure its home at Lincoln Center’s Avery Fisher Hall. “One goal of the new structure was to break down the formality of the concert hall and enhance the personal and musical connection between players and listeners. “We’re eager to bring back the populist feeling of our origins,” Lincoln Center executive Jane Moss said, citing the festival’s early days, when all tickets sold for $3. The project is also intended to provide an acoustical setting more appropriate to the sound of an 18th-century orchestra.”