Basically, my idea invilves being able to remove the cannons from the ship, and use it as a handheld cannon (same for harpoon) Itll function exactly like the ships cannons, being loadable w Firebomb, Blunderbombs, ect.
Since it is a litteral cannon, it can have tonnes of recoil, propelling you far back, and sending you flying. It requires you sacrifice a cannon on the ship, but can be put back on. Itll take up the holding slot, so you cant have a cannon and a chest at the same time, and picking up a chest will cause you to drop the cannon. It can be made so you can take a cannon or harpoon to a rowboat or island cannon mount, and mount it onto them.
It can use the skin of whichever cannon is picked up, so picking up a skinned cannon will retain the skin, and mounting it elsewhere will keep the skin, allpwing you to mix-and-match cannon skins along the ship, like how the lanterns can be colouref based on the handheld lanterns flame
As with the Harpoon, the harpoon can be recoilless, but requires button-mashing to pulk something in without being dragged yourself. Yet again, itd take up the chest slot and sacrifice it from its post on the ship or wherever it is extracted.
