There could be 3 factions, each resembling the British, French and Spanish (of course not named that way, but resembling them in outfits and ship details, like the conquistador helmet for the Spanish or the red coats for the British esque faction)
Then there'd be sea forts (similar to the ones that exist already, with the phantoms and skeletons)
Those sea forts could be capturable by each faction, and that;s how the game would start out, with no forts yet captured.
Then the factions would fight over these forts, not only for territory but for treasure.
See in the forts you'd have rooms where you could stack up treasure and after stacking a large amount up you could sell it for a hefty bonus the more there is, giving an incentive for players not only to do it, but to attack other forts.
For weapons, there could be a few new weapons:
The Brown Bess (The standard issue British musket)
The M1752 Musket (The standard Spanish musket)
The Charleville musket (The standard French musket)
With a bayonet attachment on each one, for melee.
