Another thread suggested that now that we have closed crews, could we make the brig on the sloop work, with the first aboard able to brig the other, if they join and grief.
It got me thinking. Why not allow a crew to elect a captain? This is definitely historically accurate. Pirate crews were often organized along democratic lines.
Electing a Captain
Under this scheme, a majority vote would be needed to elect - or depose - a captain. So if you create a closed (solo) sloop, you could vote yourself the captain before opening the crew to allow a stranger on board. They would have to accept your autocratic rule, or leave. The captaincy could not be changed unless the captain voted himself out of it: Which he might do if he wants to leave the game, but allow his crewmate to take over.
On a galleon, a majority of those on board (one alone, two of a crew of two, or three of a larger crew) could elect the captain. But also a majority could stage an effective mutiny and vote their captain of the job.
Powers of the Captain
Firstly, a captain could brig any member of the crew, without a vote being needed. This could make it quicker and easier to handle griefers that come on board; and allow the sloop's brig to become useful. On a galleon, he could even brig two or three crew members; albeit at the risk of losing the confidence of his crew, and his job. :-)
Perhaps captains could also have a overpowering vote on quests, eliminating the need for everyone to vote each time, and then vote to cancel it if not liked, etc.
I honestly can't think of any other game mechanics that might be changed by having an official captain (brigging was the main one), but there would be, of course, a moral authority in a well disciplined crew. He would be the one that shouts "Nor-Nor-East, helmsman" and "Adjust those sails, you scurvy idlers!"
Finally, I suggest having captains is optional. Crews may continue to sail as a self-governing autonomous collective, if they prefer to.