Great Britain spent a lot of time and effort trying to get the size of Capital Ships reduced to a level where it would be able to build larger numbers of the smaller ships. Ideally Great Britain would have liked to see the size reduced to 25,000 tons and 12" guns. On that displacement the RN felt it could build ships with 12x12" in triple or quad turrets, with reasonable armour and speed. Allied to the battleships, especially if the Germans had still built the Deutschland class ships, the RN may have needed to use some of their valuable tonnage to build a class of battlecruisers to counter the German 'pocket battleships'.
To that end this ship below and the Sud Afrika in this drawing
http://www.shipbucket.com/forums/viewto ... =15&t=5502. can be considered my attempts for battlecruisers in a 25,000 ton environment.
I will have a look shortly at a BB in a 25,000 ton level. Smurf may have some more info on these?