I would put the F-15 ! Ahead of its times in dual engine airframe design. Looked every bit sleek and sexy from sideways. Other aircrafts thereafter were mere repetitions of the dual engine / dual tails. The only other path-breaker in design was the Su series of dual engine aircrafts.
But on my own personal favorite pointer? F-4 Phantom ! I love that aircraft design - though a 3rd generation aircraft in today's terms.