One, Lignumvitae Key is closed Tuesday and Wednesday. If you are going to go, I recommend calling the park ahead of time, and making sure that there are several rangers about when you're there. I must say that highpointing in south Florida was an experience. The people there apparently mostly learned friendliness and manners from New Yorkers, and it shows. Also, if you don't like smoke in your restaurant, go elsewhere.
Many places have no non-smoking areas.
Key West is a whole different thing altogether. A VERY alternative place, full of wackos, and tourists driving little go-carts. While we were scouting the highpoint, an old man walked by yelling at us and every one else he passed. Later, another man walking down the sidewalk said hello to a couple walking down the street, calling them by name. Unfortunately, it wasn't the right name, and they had never seen him before.