Never mind multiple fins and shaving half an inch of the width of a board, if you want to be a regular in the podium your best bet is to persuade Naish to bring out an UL board like Starboard have. You are probably too big to reach the upper echelons on a 14ft board, no matter what the design.
It would be great if Naish and Starboard would go head to head in the UL division, and reboot that class.
But of course, if you want to flog yourself to death in training and spend a lot of money on racing just to watch the guys who are the size of some 12 year-olds take home the silverware, then I guess that is up to you
Even better, get a UL DW board and set your sights on winning the Icon DW race, or the French downwind ones. Dave Kalama is a pretty beefy guy and he was still able to give nanoperson Kai a run for his money downwind even at twice the young superstar's age and probably about 140% of his weight.