Smaller Japanese battleships: doctrine, fuel, and speed

Would four or five smaller battleships have served Japan better than the Yamato class?

Not necessarily: more hulls would still face fuel-processing, merchant-shipping, and doctrinal constraints, while Japan needed capital ships capable of answering Allied battle fleets and supporting decisive operations.

More hulls would still depend on Japanese doctrine and the ability to deliver usable fuel. Access to oil in the Dutch East Indies is challenged as a sufficient answer because refineries had been damaged and Japan's merchant fleet was increasingly vulnerable. Faster, more numerous battleships are defended as useful for the opening campaigns, when carriers, cruisers, and the Kongo class could keep pace with rapid operations. The opposing case gives heavier battleships a role against Allied capital ships if Force Z survives. The alternatives therefore depend on which operations and enemy concentrations Japan must answer.