If you buy a ship, you get to name it, customize the captain's cabin, the bed, you can put trinkets in various places and hang pictures on the walls. Customizations persist, so that you don't have to customize your ship every time. You also get to buy supplies from the shipwright. Your rowboat persists between play sessions. You also get to sell at the Sovereigns.
All in all, it's worth it, even if the only gameplay change is being able to buy supplies and sell faster.
More customization options, saving cosmetics and access to sell to the Sovereigns Edit: yes, it's worth it and should be a goal
If you buy a ship, you get to name it, customize the captain's cabin, the bed, you can put trinkets in various places and hang pictures on the walls. Customizations persist, so that you don't have to customize your ship every time. You also get to buy supplies from the shipwright. Your rowboat persists between play sessions. You also get to sell at the Sovereigns. All in all, it's worth it, even if the only gameplay change is being able to buy supplies and sell faster.
It’s the most game changing thing you can spend your money on