One explanation: the Ares Spanish 74 is based on Bahama but IIRC is dimensioned as her original 64-gun specs, and the Meregildos is based on the Greenwich draught of Salvador del Mundo, which was noticeably smaller than all of her sisters.

I have three Purisima Concepcions on the way myself, and if Henry ever does a Meregildos I may commission the entire class from him--I only passed on Nepomucenos because we wanted to keep the shipped package to a reasonable size/cost at around 12-15 hulls and I already had most of that filled with the PC's, class-limits on Canada and Ganges to use for a private feasibility study along with a couple Intrepids (possibly more to follow if there's another run).

Elizabeth is if memory serves between six inches and three feet longer on MD than Bellona and slightly different underwater lines, but definitely an evolution of the older design. Eventually these, too, might be candidates for "upgrade."