The Chaos fleet definitely has the greatest variety and you can either mix up some of the chaos powers or base your fleet on one deity. I have chosen to use a large variety because all the ships have their unique abilities and they look really cool. The Chaos fleet can be very powerful on the seascape but sometimes the fickle nature of the chaos  gods will bring your own undoing.

  My Chaos fleet consists of  each of the Man O' War's from all four chaos powers, a squadron of deathgallies, 2 squadrons of hellrammers, a squadron of Nurgle ships of the line the Bane Tower and a Lord of Change.