A Town-class cruiser armed with 5.25-inch guns

Would Town-class cruisers built with twelve 5.25-inch guns have been better or worse?

They would generally be worse: the gun was useful in some roles, but 6-inch weapons better suited the cruiser fights the Royal Navy expected.

The 5.25-inch gun is judged potentially useful against lightly protected cruisers and as a dual-purpose weapon, especially if developed earlier. It would nevertheless leave a Town-class cruiser less able to fight 8-inch opponents, while triple mounts would create difficult practical compromises for anti-aircraft fire.