The thing is the engine is not the limiter as many people put it. All the main PDX games use the same engine and we can see how vastly different those games are, especially when you go to something like Stelaris. While each game is obviously forked at some point for game stability we dont actually know what code has been migrated from the newer version of the engine to accomplish certain tasks. From a graphical perspective thats just polish and to keep assets looks consitant, not to mention to keep system spec requirements the same. They can always update this after a certain point, which i think would be nice, but they have the hardware stats, not us. And if you look at newer model sets they look better then the old ones where they even went back and updated some.
The real "limiter" is the size of the team, and the time they have to spend on a feature set. Its not a huge team. None of the PDX games have ginormous teams. Which means large sweeping changes take serious amounts of time. And code bases being what they are EU4 is probably huge, which slightly complicate matters.
That being said I am sure naval is on their to do list, but quite frankly unless they can come up with something that is cost effective, what can they do. Also is it actually a problem with the naval system or just naval AI.
Which leads to AI being is its own bag of worms. People expect the moon, when in fact AI is SUPER difficult in a game like this. I am sure we can have
@Chaingun,
@Wiz and others tell some fun war stories about just how crazy AI development actually is. In fact for me it would make an interesting panel video or something because many people dont have a clue, especially since we all dont run super computers.
TLDR, the engine isnt the issue. I can agree or disagree what the devs are doing is right/wrong, but lets be honest with the statement that its not the engine. That topic has also been discussed to death and is littered with misinformation from things about 32/64 bit, multi thread support, garphical support, ram, etc... Thats not to say their might not be a limiter in the actual engine, but no engine is perfect, and they have been updating this one for a long time.