Boss
You may be right about the role changes for the Valiant, indeed for the other two as well as time went on (Victor tanker and Vulcan low level…) but I suspect that in the late 40’s the notions of ECM and a major tanking capability had not yet become mainstream thinking - which at that time was simply about the bomb and how to deliver it where it might be needed.
The dates at which the three Vs first flew at the SBAC show following the 1946 spec are very revealing in terms of how quickly companies pressed on in that era. Valiant 1951, Vulcan 1952 and Victor 1953.
It is also interesting that the structure turned out to be the thing that brought the Valiant to a premature end, the Vulcan had aero probs at high mach and needed a considerable redesign of the wing, while the Victor also had structural probs although largely limited to development.
Flutter removed the tail of the first prototype Victor while Taffy Ecclestone and his crew were doing PEs at Cranfield in 1954 and B Sqn lost Sqn Leader Morgan and his crew in the B2 prototype after the pitot head fluttered off and the reversal of the usual sign of Lv at high mach (meaning it rolled right with left rudder) had them spiral into the sea in 1959.