Thanks Chel and RP for the compliments. I've done another version with the colours dialled down.
Right, enough tinkering. This one is done.
@RPMiller: there is no game room for this to be put on the wall of as all game is play are now done over the net with maptool. There's a good two sessions' worth of play in this map though, so they'll definitely get some use out of it. I'm sure the players will appreciate the craftmanship as they get butchered by pirates