The other day I was thinking of various ships and upgrades that accompany them. I eventually thought of the idea of why not having an upgrade that focuses on Broadsides? It would first upgrade your broadside count then on the final upgrade, which would be rather pricy, potentially replacing the broadside cannons with triple barrel cannons (maybe decreased damage in exchange for more shots). The trade off would be immensely decrease speed and cargo space to accommodate the additional cannons, perhaps even an increased cannon reload time for broadsides to account for the increased cannon count. It is just an idea of course.