Prepare the guacamole by pureeing the avocado and lime juice together. Add the remaining ingredients. Prepare the salsa by cooking the mango, Scotch bonnet, and wine together until soft, about 20 minutes. Prepare the pickled onion by cooking all the ingredients together over medium high heat, for about 30 minutes.
Place a small amount of the lettuce on each of 4 dinner plates, then drape the sliced marlin over the lettuce. Garnish with all three condiments.