F-60 is the original FC-31, it was just called a different name originally. It was 17.3*11.5m in dimension which as a reference is bigger than the F-35A/B model but slightly smaller in terms of wingspan compared to C model but still ~2m longer. So, it's a pretty standard sized medium weight fighter aircraft. Anything larger would probably be in the range of heavy fighters like F-22/J-20/Su-57 and beyond.