Ive really noticed that if you want to try and make historically inspired designs of say Nevada, Cavour, or KGV you are penalized for no logical reason. Several cruisers, battleships, and even a few destroyer models had this practice of a few of their main gun turrets had a different number of rifles and I've found nothing really that says this barrel arrangement was detrimental. As it stands in the game, if you try and replicate such ships you are penalized even though each gun is the same caliber and size. This really kills ladder aiming for some reason and the ammo pool is for some reason all not one thing. I believe this also hurts you if you have Wing and Centerline guns. Even though we know full well the German BCs at Jutland suffered no accuracy difficulties at Jutland due to wing mounted turrets.
As a side note Id very much like if the battleships volleyed and not just fired the guns off as soon as they reloaded.
Here's some historical examples.
USS Nevada herself, B and I believe Y turret are both doubles while A and X are triples.
Her Italian counterparts Andrea Doria and Cavour actually had an exact similar layout. They did suffer accuracy issues but not from the gun arrangement.
http://i.imgur.com/YbL8z9V.jpg
And maybe the most famous example is KGV. From everything I've read and watched about the class is the unreliability of the Quad turrets, which are mostly just a quirk of Quad guns, but her accuracy as a ship seemed more than adequate.