IMHO, there should be a number of styles of yachts available running the range of tunnage and performance. Some would be streamlined, others not. Some capable of wilderness refueling, others not. There shouldn't be any limit to the options available until you get into military type hardware.
You should have your cigarette boats, fast with very sparse accomodations, up to your Britannias, Sequoias, or Potomacs; sizable, slow, with rare wood inlays and guilded interiors. Some could even be outfitted para-military style, depending on the buyer's connections and bank account.
I would expect a number of yacht hulls to be based on the canon designs; I'm really surprised there aren't more variations on those themes, meeting the plethora of possible consumer needs.