Eh, everyone had plans but then reality intruded. Even the US, with the most resources of anyone in the war by far, had to cry uncle when it came to the Montana-class. And some weren't even practical, like the later Japanese and German designs where the guns would have exceeded the contemporary targeting capability. A huge shell isn't much good if it can't hit the target or is fired only once every minute or two.
Well, if you have 12 main guns that can fire once a minute, that averages out to 1 Volkswagon going downrange every 5 seconds.
I would be remiss if I did not include the Maximum Battleship design (biggest design that would fit into the Panama Canal) the Navy explored courtesy of my home state Senator Tillman back in 1917 (he unfortunately inflicted also us with Clemson University but that is another story...). 975 feet length, 108 foot beam, 80,000 tons, 15 (5x3) 18" rifles
