Let me say I really like how you cannot tilt the cannons left to right in BW. It makes the captain's role much more important, and simplifies the game. I do think though there may be some room for controlling the cannons vertical tilt, and switching the cannons from hitscan to projectile based.
Let me first say how it could be done with two options:
Precise: Each tilt you are at has numbers or notches, and the captain can know which number or notch gunners should turn to to fire based on his/her estimation of the range (still gunners can rely on captain for accuracy)
Dynamic: Gunners have full control over tilt, with no markings. They can use the mouse or other buttons to tilt cannon up or down. I sort of like this one cause it really gives gunners a chance to shine, and takes some responsibility off the captain and puts some skill faith in the gunman.
I know this would change some core functionality but I think it solves some problems in the game.
Hitting from long range seems fairly easy right now. Once the captain knows how to aim, you can hit all cannons fairly reliably from max range. There is still some skill in the current system though, the angles will change, they will turn away, the ocean will rock you. Also at a deeper level, if they have turned away (are a smaller target) you can keep track of what guns have not fired yet and tilt to that side so you can hit all cannons, however still this seems pretty reliable once you know what your doing.
Right now IMO, the captain is 95% responsible for the accuracy of a ship. I don't gun very much, captain a lot, but generally if my men hold fire, they will be accurate. Adding a verticle tilt feature allows them to truly feel like they are accurate gunners.
This seems like a really interesting idea, but there is always the argument, "this seems to much to rely on people to accomplish and may be too frustrating when playing with randoms." there is a lot of validity to that statement, and the simplicity of the cannons right now is so approachable. But as people get better, I think its time to put a little more responsibility on the gunners, and make them feel like actually gunman, instead of robots following the captains orders.