While fighter aircraft get faster and faster there is a diminishing return for the rationalization of the aerodynamic design. You can only build the aircraft in a "correct aerodynamic" once you have the best optimum design for speed, there is little they can do without changing the aircraft in flight or the same air. Of course, both of these possibilities have been and are being analyzed. Think of the many types of fighter aircraft, which change their configurations in flight. You have the F-8 Crusader which changed its angle of attack in flight so it could land at slower speeds, while achieving very high-speed flight. The F-111 and F-14 Tomcat both have wings that extend back in flight with increasing airspeed.
Many new designs have fighter jets "thrust vector" to help with maneuverability and quick turns, so it is as long as the pilot can take the additional "G" without fainting or implosion. The new JSF B-1 bomber and other fighters like the F-117 can store their munitions inside the aircraft so they do not hang out there causing incessant parasite drag or adding to the radar signatures of very low needed to maintain a stealth configuration. Many fighters will have additional drop tanks for extra fuel, which once used are removed. Once dropped the aircraft can then have additional maneuverability and shed the extra drag hanging below. Designers and engineers, even pilots have often thought of ways to redesign the fastest and best performing aircraft in the modern era.