What would a Roman Empire battleship look like?
Short answerIt might resemble a Littorio or Francesco Caracciolo, provided construction and ammunition had much tighter quality control.
NotesA Littorio- or Francesco Caracciolo-style ship fits the playful Roman Empire comparison. Construction and ammunition would still need strict quality control. Italian experience supplies the caution: an excellent design can produce remarkable long-range shooting with a good ammunition batch and erratic results with a bad one. Industrial consistency is therefore part of battleship effectiveness rather than a separate administrative concern.