An Atlanta-style Dido needs a larger cruiser hull

What if the Dido class had followed the Atlanta class more closely and used high-angle 4.7-inch twin mounts?

The concept could produce an effective anti-aircraft cruiser, but the Dido hull would need more length and beam, approaching Town-class dimensions, to support the extra firepower properly.

Britain could choose among 4.7-, 5.25-, and 5.5-inch weapons, so the gun itself was only part of the decision. More mounts require a larger and more stable platform than the Leander-Arethusa ancestry of the Dido design provided. Building the ship on something closer to a Town-class hull would better accommodate the armament, while a 4.7-inch version could still be an effective vessel.