Best route for leveling up your boat?

I've finally unlocked each area and I don't really care about denaro too much so I figure I'll work on upgrading my boat the fastest, which way would be the fastest?


Also, is there a list of how many upgrades the boat can go through?

I think the boat maxes at level 30, each 10 levels you get the next of the 3 skills (1-10 is cannon, 11-20 is att buff, 21-30 is arrow rain), and i think it was said somewhere here today that the levels for those skills reset when you upgrade the boat.

I don't know how boat exp works but i would imagine the higher areas do it the fastest.