you can also directly mod the weapons themselves using HxD to edit the resources.assets file. I've figured out how to change range and rate of fire, but my programming knowledge is far too meager to figure out the rest of what I KNOW is in that file, like accuracy, melee, production cost, or anything with the boats like gun decks' number and size of cannons, HP, thickness, and base speed. Only worth doing on faction specific weapons tho, like the virginia musket or the brown bess '76, since any changes you make will affect all units armed with that weapon, including enemies.

Increasing musket range from 500 to 2400 makes infantry able to stomp the hell out of easily 3x their number without taking any casualties in return. Add in some buffed reload and a single company can take down an army. Cannons are definitely limited by the reload animation speed though, no matter how fast you set their reload they cant get faster than the animation allows. Muskets may have the same problem to a much less noticeable degree. I havent tried modding naval cannons, since every gun is used by enemy ships except the 4pd and without being able to mod the penetration and damage values, that gun is just too weak to use as a base.