When you head to Homestead I highly suggest going to RF Orchids and to Richard Lyons Nursery---both are awesome! And Fruit & Spice Park is definitely not to be missed! Take the tour, you'll be able to eat samples of what is in season.
In the Keys, stop at the Keys Wild Bird Center on the west side of Key Largo--might even be Tavernier at that location.
There's SO much to do in S. Florida, I think you'll have plenty to keep you entertained!
Definitely do Loop Road. It can be potholey and bumpy, but it just makes slowing down all the more worthwhile. Plan several hours for that trip and stopping. You can hit up Chokoloskee after for a meal.
I could go on and on for days about Florida! ;)
