As much as I like ramdom events, to many can break a game and rob any skill requirements in order to win.
Mario Kart Wii, Super Smash Bros Brawl are good examples of complete ramdom chaos changing everything so regardless of skill level or tactics used, You can end up losing. But those are designed for that and are fun because of it.
A stratagey oriented game like Sins probably would't do so well.
One thing I do want is stronger pirates. I agree that they do little more than annoy by end game.