May help for single player. Could be bad if you're trying to go out. With teams, the ability to "Merchant Flood" makes it less necessary, and probably quite overpowered.
I should probably clarify. In team games, having everyone on your team flood the sea with merchants just as your enemies get snarled in a big battle is a pretty powerful tactic, so if each of you got to draw a card on top of that it might just break the game.