I never got to fly the Vulcan, sadly, but I was deeply impressed by Black Buck and found Vulcan 607 a riveting read.
On the question of fuel burn, was it necessary to fuel to such a high level each time? Would it not have been better to try to keep the weight a little lower and fuel burn lower too?
I know that the old wisdom is that you can never have too much fuel - but maybe in this case you could!