Really depends on what type of sailing/crew you will be most likely to have. Obviously, there is a large and growing I-20 fleet in FL (12 active and traveling racers at this point). Several Tigers have appeared as well, and I have seen one or two at some of the marque races.... If you're on the lighter side, it's a tossup as to which would work best. I typically end up on the lighter side (with crew), and have an I-20, which is fantastic until winds over 15 mph. My heavier crew steps in and we're all set if that happens...
Also, there are some great distance races in FL, so think about hitting those if you have time. Check the NOR (notice of Race) on the Catsailor website for info on those...
Tiger, I-20, N6.0, M6.0... they're all solid boats, so you're sure to be in good company with whatever you feel suits you best...