Inspired by Nigel's discussion of 1915+ battleships, I've bumped up the Design U4 on my drawing list as an Easter egg for you all!
Design U4
Design U5
The U series began as the 'Canadian Fast Battleships', the extra Queen Elizabeth class ships that the British government tried to convince the Canadians to finance. There were several other fast battleship designs within this series not intended for funding by Canada, sources on most of these seem very sketchy and few details are known.
U1 and 2 were very similar to QE with a nominal speed of 25kts. U3 was also similar with one large single funnel. U4 had all four turrets on the same level to overcome problems with early directing of turrets at different levels. U5 was similar but with the forward turrets en echelon to give bow fire. The main belt was reduced a 12in with increased deck armour.
It seems that the 1914 improved QE, Agincourt, may never have been settled and D.K. Brown suggests eventually she was substituted for a repeat QE. The Us seem to be influenced by the W1 and W2 designs based on the Royal Sovereign (as I've drawn before) with the same double-deck battery, larger conning tower and stem spotting position.
Now for the caveats: the only drawing I've ever seen of U4 is a plan drawn by John Roberts, presumably from the original sketch. His sketch lacks an underwater hull. There is no data on length but this ship seems to scale up correctly to 620 feet oa (the same as the W1 and W2) and I've taken the liberty of adding a R-style underwater hull. There are no belt armour details so I've based this off QE and R. There is no image of U5, but I've assumed the only change would be B turret would face forwards.
Maybe one day when I redo the QEs, I'll have a bash at the other Us, but they too would be artists interpretations.