Or fit them with updated Red Top missiles, as used by Lightnings.
I can't really see the F8 as a contender for many of the reasons outlined, unless the number of F8s vs F4s that could be embarked were far greater (which I'd doubt) to improve sortie rates to counter their deficiency in radar and armament: F4s had better radar, better weapons, more scope for modernisation, longer range. (And numbers of missiles carried was important, given the poor kill ratio of the then radar-guided missiles: can't really just do with two of them, even if used just to scatter an approaching formation before zooming back on them to fire off close-range AAMs.)
And, politics/economics aside, I think the Buccanneer was a superior maritime strike aircraft to the A7 Corsair (which was very good in its own right), given the role the RN earmarked for it, so I can't imagine the RN going for second best in fighter and strike carrier aircraft for a marginal increase in air complement.