I find it quite odd that these designs are twin screws, while the Leander class as built had four screws. IMHO design C was the basis for what became the Leander class and as such would it be more logical to do it as a 4 screws ship?
IIRC most of the RN cruisers were 4 screws ships (apart from the C class and D class of WW 1 vintage, as these were originally designed with destroyers' engine plant)
Actually, if you look closely, there ARE four screws in the lineart picture. Oops...
Oooh Hoood, you made a bit of a mistake...