>>96756490
The idea of sailing between islands with your party on a ship appeals to the sense of wonder and adventure, while evoking a variety of aesthetics ranging from age of sail pirates to vikings, and keeps things fresh by having the party able to constantly travel.
From a gameplay standpoint, it provides the group with a mobile home base they will get invested in both narratively and in terms of game resources. It gives a great excuse to have varied locations and provides an easy means of doing adventure of the week style games, or at least contained mini adventures, by having the party sail from island to island doing various things. Perhaps one day they arrive on the island city state of Totally Not Venice and get involved in merchant guild shenanigans, and then next time they sail to the island of Lizard People Lovecraft Cultists, and then after untangling that mess of tentacles they sail to the Bay of Bodacious Beach Babes.