Plot: As for plot I'd go more with privateering.  That way one can be "good guy" pirates.  You may rape, pillage and kill but they're only people from a country we don't like and are sorta, almost, at war with.


Magic: I would lean into the idea that magic is more like "real world magic" and takes many minutes or even hours to cast making the usage of it in combat mostly pointless.

"Sure, I'll summon a kraken to take on their ship.  I just need the bones of a drowned princess, thirteen teeth from a shark and two days to prepare.  Anyone have any drowned princess bone?"