Gloves are also not a bad idea, especially if you keep a tight grip on your booms. Bring a rashguard. They generally chill you but you might want it for sun protection. Bring Gloves, duct tape, and new skin for your hands. Bring sailing booties.
Sea urchins are no fun in the feet.
If you wear contacts or glasses, bring your prescription with you in case you lose them. If you're bringing sunscreen, as opposed to buying it there, get the Waterbabies type in the pink bottle. It's the only type that won't burn your eyes. A ball cap is nice to shade your face. Depending on how long you're staying, you may want to coop reading books so that each of you isn't lugging down four or five.