Why Britain might combine specialist support functions

Would a British Empire that retained greater power build equivalents to American missile-range, satellite-communications, and ballistic-missile support ships?

Possibly, but Britain might combine some of those functions in cruiser-style command ships rather than copy every American auxiliary type.

American-style missile-range, satellite-communications, and cargo ships are possible British equivalents, though they are not inevitable. A surviving larger fleet could organize the same functions around its own operating preferences. Britain's greater inclination toward cruisers makes a warship-based command platform a plausible alternative to a dedicated communications auxiliary. Read with the earlier crewing discussion, the distinction is between specialist support hulls suited to the RFA and command functions important enough to remain in a Royal Navy warship.