Well I can at least do some more efficent exploring, I used to just drag a straight line whenever I had some free pirates. xD
And if you equip with a couple of buccaneers and gunners, you can also attack low level ships to collect additional battle points.
@Cap'n Creeperb Well, now that you know... when you're doing a trip, obviously follow the water colors, but also look at all the possible alternate routes. Sometimes a route that appears to be the long way will end up being much shorter, be it due to a longer duration over lighter water, or avoiding a monster, or a few squares of that evil dark water.