i like the uncharted waters model to but have a market hall with stalls instead of people on mats every were tea shop/taven were you can get ship insurance and hire new crew from. i like to be able to walk over and barter for my goods check out the market advert boards to for work/job offers for other people
smaller towns have an open air market
bigger towns have both open air and indoor market hall
pirate towns have black market goods/back alleys sell cheeper no crown tax or fees just a dangerous location
hire a stall for 24 hours fill it with goods and leave or stay there and push your products barter
and the plantations, own towns were a good idea i would like to see player made ports/town a reason for companies/guilds to fight for water trade routes,gold mines,ore mine,tea,tobacco,spices,silks etc....etc
that way companies will patrol water that there trade ships use and the enemy uses pirates will the chance to hunt traders on these high risk high reward runs or even pick of a few battle ships here and there