My Clanmate and I came up with the idea of being able to melt down crafted or looted cannons. Prices in harbour shops are so low you can't really make an income out of them.
Since we're able to break up ships and get some materials out of this, i can imagine melting down my stacks of med6's and med9's i collected while looting and capping for some iron ingots and the small/medium/large carriages they're built with. Maybe even brings more people to crafting, because resource buildings are no longer must have and buying off the market not a must do. On long term maybe even cannon prices overall could drop, which makes outfitting your ship cheaper, and cheaper ships are more easy to be replaced ;-)