well, they mantain that there is no reason that someone would build a outdated ship when you have better tech.
One word: Congress.
https://en.wikipedia.org/wiki/Mississippi-class_battleship
Latest PreDreads are 16,000.
Everyone is moving up to building 20,000+ Dreadnoughts.
Congress' answer: demand 13,000 tonners be built that cannot do anything because they're too slow and short ranged that linger in the USN doing nothing until sold to Greece at a loss, because smaller = cheaper in their minds (Hint: Smaller is rarely, if ever cheaper with navies. Either the ships are useless when it comes their role, or if you're going for numbers, 2 slightly smaller warships are far more expensive than one larger one and are only good for covering more ground, like Britain protecting their colonial empire and convoys. It's also for that reason, and many others, that the US builds giant carriers instead of small ones like other nations, they're more bang for their buck).
That said, I'm now quite curious if Beastro can suggest a model or a ship we should ape. We have up to 13 inches guns on triple turrets, a max dock size of 25'000 (30'000 if we build in Britain) and the tech to have five centerline turrets.
There is any historical ship that we can crash test as the new Flagship of the Tsarist Navy? Or we can go and try to build a Battlecruiser or two. They are kinda cheaper than proper BBs, and we have the tech for them.
I don't know enough of the game and how simulationist it is. Like the Ganguts (
https://en.wikipedia.org/wiki/Gangut-class_battleship) that were built historically look odd and not as good as contemporary dreadnoughts of the time, but that ignores the fact that they were specifically designed to operate in the Baltic and to use that unique environment to it's advantage, which is why they have very little super structure and non-superfiring turrets (superfiring is the term for a turret sitting above and behind another meat to shorten the hull and turret/magazine protection making the ships shorter and lighter for what they carry, a very good idea), so they could be as hard to hit as possible while still fielding as many guns as possible in what was looked on as a knife fighting environment.
It's for that reason that the layout didn't make a return in the Black Sea Dreadnoughts, but did when they decided to build a class of Baltic Battlecruisers, the Ismail class.
I also don't know what mechanics are at play in the game and I see you operating well outside the Baltic. And I don't know exactly what you want the ships to do, like do you want them for a Pacific Fleet or as a detached squadron to operate on its own.
For a baseline, I'd recommend the first British SuperDreads, The Orions which are about that size you can built,
https://en.wikipedia.org/wiki/Orion-class_battleship
I'd recommend modifying such a design to delete the amidships turret (limited firing archs, is very restricted in what it can do compared to what it prevents a design from accomplishing without it) reducing the armament to 8 13 inchers and putting the extra tonnage into more speed or better protection.
If you want to go super hindsight, then just have three tripe turrets, two forward, one aft, which provides the best balance of armament, weight and protection. Four twins, two turrets forward and aft have less protection because they lengthen the ship and require more equally protected which means less armour if you don't want speed to drop. More turrets also increases the chances of a turret being hit and knocked out not to mention the possibility of a magazine being penetrated. They do offer slightly superior firepower, allowing for a balance of 4 guns for each end and four guns split evenly if a battleship has to focus on two targets, on a 3 triple one target gets 6 while another only gets 3.
I also don't know if this game simulates combat enough to factor in nuanced bits of naval warfare, like the fact that a warships accuracy degrades when under fire for various reasons. Because of that it's a good idea to split fire to make sure all enemy ships are being attacked to prevent one the luxury of firing unmolested. Exs: If one ship goes again two, it's a good idea to split between both or with two fleets of multiple ships, make sure all are being attacked while having the majority of turrets focusing on one or two ships to try to work on progressively knocking each ship out.
4 triples I don't think you can pull off decently on 25,000 tons. The Austrians tried on 20,000 and their Dreadnoughts were simply too much put into a small package, the Ganguts were slightly more then 25,000, but sacrificed armour for a bit more speed and their unique turret lay out.
Still I think like the Viribus Unitis' a 25,000 ton design will be slow and/or not have great protection to pay for that extra turret (I'd rather have 9 guns and 24+ knots, which is effectively the endgame of battleship design everyone settled on, which are Fast BBs in all but name).
A good rule of thumb is to do what everyone else did back then and settle on a speed limit to build your entire fleet around, then up the speed a bit and settle on that as the new one. That way you won't have 18, 20, 24, 26 knot ships and find the faster ones stuck fighting alongside the 18 knoters making the speed irrelevant.
PreDreads seemed to settle on 18 knots as their max (which was the upper level tripe expansion engines could do do with their level of armament and protection) while Dreadnoughts and Super-Dread went to 21 and the proto-Fast battleships (Queen Elizabeths, Nagatos, and Nelsons) bumped it to 24-25 knots.
To summarize:
-thick armor on the belt and conning tower, less armor on the decks, turrets and batteries.
-5 twin turrets with the largest gun you can fit (13"unless the 12" are for some reason better)
-small secondary armament
-high speed to chase enemy capital ships or get out of harms way
Grimgravy is right, get more turret armour.
Unless you have a good fleet of destroyers and cruisers to escort your battleships its good for them to have a decent secondary to tackle smaller warships. Dreadnought had a paltry secondary armament for that reason, but the RN quickly realized their Dreads needed a decent sized amount of 4-6 inchers to deal with destroyers and cruisers on their own.
If you insist on using 5 turrets then I recommend using a modified layout like HMS Tiger had where the aft superstrutce is cut down/removed to improve the firing arcs of the "Q" turret (amidship turret):
For a battleship you'd place a turret between the two aft ones (which on Tiger was occupied by engine space below).
For speed, find out what the typical speed of your enemies is and built your ships a few knots fasters. Again, I don't know how the strategic gameplay is like, if there is any.
The USN went for one extreme where they completely ignored speed and made their fleet entirely 21knot battleships since they planned around the larger picture of knowing where battles would take place and designing their ships to battle there, in their case they expected war in the Pacific around the Philippines or Marianas so while those held out they could limber over with a super navy in other respects and smash the Japanese who either had to fight or use their speed to escape and surrender the battle to them allowing the US to their bases in the Western Pacific to then sail for Japan and press battle once more. This is typically viewed as the Mahanian view of navy warfare.
The Brits and Germans focused on a battlefleet very similar, but backed up by a fast wing of Cruisers, and then Battlecruisers. The Cruisers would scout and screen the battlefleet while the BCs protected them from ACs and BCs. As it went in WWI the Scouting forces got more action due to their speed and found themselves "tying" up the enemy: Jutland was essentially the two scouting forces meeting and deciding where the battle took place keeping other in place for their respective battlefleets to lumber towards, effectively a naval version of the old "hammer and anvil" armies using slow infantry to pin enemy armies to allow cavalry the chance to circle around and smash them from behind.
I don't know how the game plays out, but since you only have ex-German colonies in the Pacific, it sounds like you're still based out of your two main bases on the opposite sides of the world, the Baltic and Manchuria/Eastern Siberia. It means you 'll know where the enemy will attack while you can focus on choosing where to attack yourself without having to protect anything. It leaves you free to decide to choose either slow, power fleets or something with more finesse.
Were I in your place I'd recommend building a fast wing that can be easily sent to the Pacific to fight to reinforce it and harass the enemy in batteries by getting in front of them and forcing them to change their direction, but that's my bias showing.
What is your fleet disposition like atm? I get the feeling your have almost everything in the Baltic and only scraps in the Pacific, which will switch when you decide to go to war with Japan. Have you thought about eventually building a permanent Pacific Fleet?