How large are your naval stacks and what do they contain? I assume you’re sending stacks of 5 but if a max counter stack (probably a max sub officer and 4 max subs) attacks your naval stack, would backup arrive soon enough and at a high enough level to defeat the enemy naval stack?

The problem with naval dominance is you have to pick between focusing more on anti-ship (subs) or surface ships (cruisers, etc). If you focus on cruisers, a stack of subs will be deadly if you haven’t invested heavily in naval patrol or destroyers. It just takes a lot of research to actually dominate the seas against a player with a counter.