Even though the look of a modern F1 car is regulated to the millimeter, the basic design hasn't changed much in years. While Fangio might not recognise a modern F1 car, James Hunt certainly would. Front and rear wings, side pods, mid engine... these were all changes done to gain an advantage. I miss that aspect of the sport.
Maybe for 5 years instead of cookie cutter cars designed to fit templates, just let the teams do whatever they want. There will be some great new ideas, as well as some awful ones. The sport will leap forward, and our idea of a 'racing car' will will too. Certainly cost is a factor, but it's cheaper to try something unique than simply test 100 slightly different variations on the same thing everyone else is doing.