The Bucc carries fewer, mostly from the light rated underwing pylons, but offers greater performance with penetration at high Mach and low level instead of medium Mach and medium level.
I have a feeling that the Buccaneer was originally designed as as a specialist nuclear bomber to attack Sverdlovs. One nuc carried in the rotating bomb bay and not a lot intended to go onto the wings.
The intention being to go as fast and low as possible. As I understand it very few modern fighters were able to catch Buccs going fast low down in the Red Flag exercises - at least before the wings fell off!