Heat the oven to 400 degrees. Arrange the corn chips on a large baking tray. In a large bowl stir together the shredded chicken, ¾ cup sour cream, ½ cup salsa, green onions, fajita seasoning mix, and fresh lime juice. Mix well. Spoon the chicken mixture evenly on top of the corn chips. Sprinkle the chicken with the black beans, banana peppers, and olives. Top with shredded cheese. Bake the nachos for 3 to 5 minutes or until the cheese is melted. Garnish with avocado slices, the remaining salsa, and the remaining sour cream. Add the jalapeno peppers for additional flavor, if desired.