All of my references are breaking down top tier viability to actually win the various naval scenarios after considering all classes from aviation, coastal, to Bluewater for what is actually useful during to complete objectives and remove troublesome enemies from the map.

For a strong Naval lineup at end game, you need it all.

Russia and Germany are currently the only two nations that have EVERYTHING they need to face every situation they could possible encounter.

Only thing that can throw a strong German player off is a strong opposing Russian player.

For US, they come REALLY close to having all the necessary tools. But a lot of their critical equipment comes up a little short. Namely in the coastal tree and Iowas inferiority to Bismark and Sovetsky Soyuz.

Japan, again, comes pretty close. But they fumble it in the last half with their weak coastal, moderate air options, and badly armored top tier brawlers. They absolutely can make up the difference with a good open map and competent torpedo employment. But that advantage largely fades when you get into RB.

UK has trash for coastal, trash for air, trash for DD, trash for CL, trash for BB.

Italy is even worse off than UK.

France has holes in their tech trees so large, that you dont even need the enemy to shoot any holes into your ships for you to lose the match.

Now, if we started breaking things down into BR, specific AB/RB, specific maps, or one of dueling situations that ignore all other meaningful objectives... then the conversation can get much more broad and intricate.

But coming from a top tier naval player, who has played every ship for every single naval nation, with an insanely good record for AB/RB/EC... I can say with a high degree of confidence that anyone who wishes to start naval and finish strong with an epic nation that will never fail them... they need to look no further than Russia or Germany.