I would have to go for the Yamato . Her armament in 1941 was : 9x18.1 inch Main guns ( the largest naval guns ever fitted to a battleship) , 12x6.1 inch , 12x5.0 inch , 24x0.98 inch & 4x0.52 inch anti-aircraft guns . In 1944/1945 she was re-fitted and re-armed , so her armament was 9x18.1 inch / 6x6.1 inch / 24x5.0 inch / 162x0.98 inch & 4x0.52 inch A.A. guns. It was a combination of poor decission-making by the Japanese Admiralty , lack of resources ( Fuel etc.) , Loss of air superiority , and America's ability to decipher Japanese codes that stunted her ability to perform to her maximum capability. Her sister ship , the Musashi , was also very impressive too.
Hood , although an impressive vessel , had been compromised in her design by the Admiralty . They had specified that they wanted her to be a fast Battle Cruiser , so armour was lightened to give her a top speed in 1920 of 31 knots. When she was sunk by the Bismarck in 1941 , she was over 20 years old but had been re-fitted , but her maximum speed then was 28 knots. Her armament was 4 turrets of 2x15 inch main guns / 7 x 2 QF 4 inch Mk.XVI anti-aircraft / 3 x 8 QF 2 pounder "pom-pom" anti-aircraft / 5 x 4 - 0.5 Vickers machine guns / 5 x 20 barrel "unrotated projectile" mounts / 4 x 21 inch above water torpedo tubes.