That idea works, but i love the excelsior and i think we should have seen more than 2 excelsior II's. and even one of those was an accident...
Thanks for answering my question!
It might be helpful to think of the Enterprise-B
as a variant then, and a rather uncommon one designed with a specific, rather uncommon mission goal in mind, rather than a refit. I do.
Maybe it has something to do with how adaptable the Miranda Class was, due to modular construction. We know it has interchangable mission pods for the "rollbar", but maybe that's not the only modularity to the design.
Indeed, those big shuttle/cargo bay doors and various greeblies in the rear section almost beg
for a high degree of modularity.