You should have a mop and a broom along with bucket to swab the deck this would give players something to do on long voyages around the map and long with the mop and broom you should have to tools to scrape barnacles off the underside of your ship, here are some examples of what these tools could be used on.
When you puke on the deck you'd have to eventually swab it off or leave it there, there could also be wet sand or mud as well as dry sand and dirt from walking ashore and back aboard to swab as well as salt from the water, as well as blood from when you get hurt aboard the ship, and if you have animals aboard the ship there could be excrement left behind along with scales and possibly feathers depending on the animal.
It may not be the most important thing to add but I'm sure players would appreciate the depth and realism it would add to the game and the task of keeping the ship clean.
