Would an N3 built with four triple 15-inch turrets be better than the historical design?
Short answerProbably in firepower: it would carry twelve rather than nine guns, likely split six forward and six aft.
NotesA four-triple-turret N3 would have more gun power than the historical nine-gun design because it would carry twelve 15-inch weapons. The expected arrangement places six guns forward and six aft, distributing the added battery between both ends of the ship. The question supplies no calculation of the extra turret's effects on displacement, armor, magazines, machinery, or hull dimensions. This is a concise armament comparison rather than a complete assessment of the redesign.