A bit of a tangent, but I felt like Rule the Waves 2 has an interesting approach to that. You can have a decisive fleet battle that wins the war for you, but the wars themselves are less decisive, strategically. You win the war and gain some reparations and new colonies. A good portion of the enemy’s capital ships are on the bottom of the sea. But now you need to spend more of your budget to defend the new colonies and maybe the government doesn’t see your vanquished foe as much of a threat anymore so they may cut your funding.
Add to that ships that rapidly become obsolete and the decisive advantage you got by sinking a few of their battleships can erode over years of peace, and economically weakened foes that have a grudge against you can later team up to pose more of a threat.
That’s a very different sort of game though.