Unpopular Opinion: I don't want Paradox to add navy to the game
I know it would be more historically accurate to have navy represented in the game, but I am really worried if it is added, it would just add a lot of unnecessary hassle. Part of it is that I don't trust Paradox to do navy in a way that would be fun, considering that every other Paradox GSG has a really, really tedious navy system (especially CK2 and HOI4).
In fact, one of my favorite quality of life features coming to CK3 was the fact that I didnt have to waste a bunch of time building ships, raising them, moving them next to the army, embarking the army (which almost always didnt fit on one trip meaning I would need to do multiple trips), moving the ships next to the coast and then disembarking. Just to land a simple naval invasion. Instead, I could just tell the army where I wanted it to go and the army naval invaded on its own.
Again, I know that it is historically inaccurate, and there are some ways to make it more representative of history (like making troop embarkation a tribal innovation that the Khazars don't have access to at the start so they can't invade Constantinople). But overall I don't think exact historical accuracy should come at the cost of enjoyable gameplay. Ck3 isn't EU5, it's not a simulation. I would much rather just tell the army where to go and then they go. Even other games like Civ6 do this exact thing and nobody has an issue with it.
Anyway that's just my personal opinion