Well, for a tropical paradise, go to the keys, You can camp, or if you aren't in to camping, they have hotels.
As for a FALL fall, I would suggest the Piedmont in SC, or NC, some of the most beautiful scenery ever!
They have fewer bed and breakfasts, but they are smaller, and cozier. And if you find the right location, you can look out over waterfalls, rolling hills of oranges, reds, and browns. Also the weather isn't friggid, but it isn't broiling, like light sweater weather.
But plan it carefully, because if you don't, you may run into some nast rains, where it won't be pleasant, at all. :-