Headlights gets a new look for the first time in 20 years, and some members are calling it the best issue ever published. Eric Oszustowicz, author of “The Elevated Railways of Manhattan,” answers the question of how the Second Avenue Subway might have turned out had it been finished 86 years ago in “The 1931 IND Plans,” his exclusive examination of actual SAS blueprints. Then John Pappas compares the new streetcar systems of Cincinnati, Kansas City and Granada in our gorgeously illustrated cover story, “A Tale of Three Cities.”