When the DP 6" comes along, assuming the war carries on long enough, you could replace the 6" with those... or you could simply put 5"/38 turrets onto those barbettes, like was done with the Wyoming when she was a gunnery training ship (AG-17)...
I agree; however, the 6" DP guns were not designed until 1943 and did not enter service until 1948
NavWeapons states
"These guns did not prove reliable in service, possibly because of the high rate of fire and need for any-elevation loading. Another contributing cause was that they used a dual projectile hoist system - one for AP and one for HC/AA shells - which proved to be a source of jamming. And the dual-purpose performance came at a steep price in weight, with these twin turrets weighing about 20% more than the triple turrets used on the previous Cleveland class. In this regards, it should also be noted that the late-war equivalent 5"/38 (12.7 cm) armed Atlanta class AA cruisers carried the same number of guns on less than half the displacement of Worcester. In other words, two Atlantas carrying a total of 24 of the excellent 5"/38 (12.7 cm) guns could be built for less tonnage than one Worcester carrying half as many guns, albeit more powerful ones."
They go on to say that a triple mount would have had a theoretical 20-25 round per minute rate of fire.