I have one of each ship type and cycle through ship cosmetics almost as often as I do for my pirate, so I don't have theme naming for any of them. Originally had the idea for "Grim's Fortune" in honor of my gamertag, but then I realized that was the name of the ship with the Veil Stone on it in every ship graveyard in the Legend of the Veil voyages, so I scrapped that idea and settled for some kind of cool-sounding sweatlord title on my sloop...for about a week and half. Then I found I couldn't take myself seriously sailing it!!
So now, you can find me most days out on the sea at the helm of my fair sloop, The Grog-Knobbler.
My brigantine and galleon don't leave the Outposts terribly often unless I've got a full compliment of friends with me (a rarity in itself), but the brig is aptly named "Briggin' Ain't Easy" and my galley, "That Sinking Feeling".