Yeah the boarding ship was an attempt to basically be a water monk. The scout ship was basically a scout cavalry. good vs boarding ships.
While it’s not 200 IQ problem solving, Romae Ad Bellum team did realize that trying to copy the land counter structures would be a good starting point.
I will say tho, that I think the biggest thing that is needed, is just one more ship type that replaces the demo in the water triangle.
Lanchester’s square law says that units that satisfy a certain set of assumptions will have their offensive capability grow in a squared relationship to the number of units.
So if you and I have 10 galleys each, we patrol, nothing fancy, our navies cancel out.
Now if I double the number of galleys I have to 20 something interesting happens. You’ll still lose 10 galleys, but I won’t lose 10 galleys, I’ll lose maybe a 3-5.
Now no aoe2 unit PERFECTLY satisfies all the assumptions, but ranged units get pretty close. Units with short/no range still have their strength increase at more than a linear rate, but it’s not the full exponent of 2. usually around 1.5 - 1.7.
This is why knights and archers in low numbers favor knights, but at larger numbers the advantage goes to the archers. Archers basically satisfy all the assumptions, so their offensive capacity grows at an exponent of 2, but knights which don’t satisfy all the assumptions, only have their offensive capacity grow at an exponent of about 1.7. Beyond micro, the archers increase their offensive capacity with additional units at a greater rate than do knights. There’s a tipping point, and suddenly the archers are the stronger army.
Similarly with galleys and fire ships.
However we come to a big problem with demos. Their suicide area of effect attack kind of breaks the rules. When you do the math and the experiments, as SOTL did many years ago in a water triangle deep dive, demos basically trade 1 for 1 regardless of the relative size of the navies. A lot of variance can occur between encounters, but the trend is that a demo can be expected on average to destroy one enemy ship.
This a fantastic catchup mechanic. You try to build a new navy of galleys against your enemies galley’s and the expected value of your galleys is basically nil. Lanchester is favoring your enemy so hard that you’re just throwing away resources. But going for demos you aren’t punished the same way. If you can produce demos faster than your enemy can produce galleys, eventually you’ll win, and then you can transition to galleys.
The problem is, demos are a terrible investment if you’re already in the lead. because they trend towards a 1 to 1 trade regardless of the relative navy sizes, if you’re making demos, the offensive capacity of your demo navy grows approximately linearly. Whereas if you were to invest in galleys or even fire ships, the strength of you army grows exponentially, between an exponent of 1.5 - 2 depending on the unit.
So, generally speaking, the best time to make demos is when you’re already losing. You don’t want to make demos to win water, you want to make demos to stop losing water. So the unit that is supposedly there to counter fires, only provides that utility in situations where you’re already losing. Let the fire ships take water, then consider if it’s worth it to invest in demos.
To sum it up, aoe2 water is like playing rock, paper, scissors, but instead of rock beating scissors, rock only doesn’t lose to scissors.
If there was a third kind of ship that actually was the third part of a water triangle, then then fire ships wouldn’t be the only ship you saw on hybrid maps.
Yes there’s a lot more nuance that can go into it. civ matchup and bonuses, specify map type, micro ability, unit resource cost balance, etc, etc, etc. But presently the current water design doesn’t allow for a functioning triangle to even be among the set of possible outcomes.