I began a new game with four players, and the main theme is : Pirates!
My goal in this campaign is to focus on rp, exploration and giving the players more agency than ever (a sandbox, if you will). I'm looking for ideas of sea-based adventures for my players; do you have any ? I'm also curious on what is your view of a campaign where the players are pirates. I already have in mind the inclusion of a few adventures (re-worked for the world of the campaign) of Ghosts of Saltmarsh in mind, but I search more.
(For more context : The campaign sets on the Nomad Lands, an archipelago. At the center of it, the religious captial of Toram extends it's dominion over the Nomad Lands, but not entirely. I suppose the main interest of the players will be the the lands outside the dominion, where tales & legends of the people come to life.)
I ran a years-long fork of my Ptolus campaign set in Green Ronin's Freeport, which also included Goodman Games' Tower of the Black Pearl, Atlas Games' Maiden Voyage (strong,
strong recommendation for this one), the Freeport Trilogy, Goodman Games' Bloody Jack's Gold (skippable, unfortunately) and Vengeance in Freeport. I also strongly recommend the system-neutral Pirate's Guide to Freeport (set after the Freeport Trilogy, but easy to use despite that, and a much better setting than the earlier, often very silly Freeport: City of Adventure).
I also ran a mini-campaign for my dad, who decided his bard's background was pirate and wanted to lean into that, which sent us from the docks of Ptolus to the Isle of Dread (Goodman Games' OAR edition) to a bunch of haunted islands in between. (He and his companion robbing a treasure chest in undead-filled flooded tunnels and having to outrace pursuit, looking for air pockets along the way, is an all-time D&D highlight for me.)
And even if you don't play it, but just use 5E, it's worth picking up Pirate Borg, which is stuffed full of random generation tables that allow you to create a satisfying pirate adventure in less than three minutes. There's also a 5E conversion book (might be PDF-only) and naval combat rules from Limithron that I'd definitely pick up.
There's a ton of support for 5E piratical and nautical adventures, often from very good creators. Nowadays, I personally would just do it all in Pirate Borg, but that's a very particular flavor of pirate adventures (Evil Dead + Pirates of the Caribbean), and it's hard to go wrong with a pirate-based campaign, IMO, as long as everyone's on the same page, tonally. (I was in an abortive 5E pirate campaign that was extremely grim and mean-spirited and no one seemed to be having much fun.)