What they have in common is being small cruisers dedicated to the role of destroyer leader/AA-ship. Atlanta was at least technically built as a destroyer leader - hence her high speed and torpedo tubes - but the USN soon discovered she could paint the sky with 5" shells as well. After a brief stint escorting convoys and fighting battleships (unsuccessfully) off Guadalcanal, the Atlantas were mostly kept in company with the carriers and the torpedo tubes were removed. The later ships of this type took off the 5" twin mounts on the sides. Like the Didos, they could pile 3 turrets high - quite a sight in profile.
The British first converted some of their WW1-era 'C'-class cruisers to an AA role and found them very useful. The Dido-class (have to be careful with that spelling) were intended to mount 5xtwin 5.25" dual-purpose mounts (same as on the King George V-class battleships) on a very small displacement - around 5500 tons to start with, though like every other ship of the war they got heavier.
Shortages and delays in providing the 5.25" mounts meant they were completed in a variety of ways. Some had the C turret replaced by a 4" AA mount, some had 4xtwin 4.5" AA mounts (a better AA gun but not much punch in a surface engagement) instead of the 5.25". The follow-on class (Bellona) basically left off the C turret (for stability and weight) and added more light AA. Very good ships - very useful - were in a number of actions and acquitted themselves well, but 5 - half the original class - were lost or so damaged they were condemned.
This is a fine example of 'knowing when to stop'. Instead of building (and risking) a 10,000-ton cruiser for every mission the RN built a 5,500-ton cruiser of limited but real value - very efficient.
BTW, the photo caption is, "HMS%20Phoebe%20Arriving%20at%20Valetta%20Harbour,%20Malta%201949".
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