Robollax

I'm fairly new to the game, but I've noticed that in the end game tech levels, some nations are much better than others. I can kind of get why only some nations have access to the super battleship hulls (although not the french hull that appears to be based on the Hood as their super battleship). But I don't really follow why some nations get the modern battleship I and II and some end at Modernised Dreadnought and the British get the weird N3/G3 Hull which is a slightly worse Modern battleship? I'm confused mainly because if this follows through to the campaign, how do nations like Austria-Hungary or China compete with 1940s tech, nevermind the British?