Here is my
newbie perspective for sailing the keys.
1) The coastal areas are VERY shallow. In a lightweight
trimaran, you should not have any problems. Keep in mind, though, that in some protected areas you can be fined for running aground
2) The shallow areas run far from shore, so you will want to keep any daggerboards (if you have them) retracted unless you are in clear
blue water
3) If you stick to marked channels approaching land, be aware that the channels are VERY snakey... it can be tricky to figure out where the channel begins , and in which direction it runs. A good detailed up to date chart plotter is a big help in this regard. Visually, the markers appear to be randomly scattered about until you are actually lined up on the channel!
4) The keys (at least where I was) are not a sandy-shores kind of place. Most shores are crowded with mangroves. Harbors are very expensive places to stay. The backwaters are so shallow that, even where there is a beach, you may need less than 2'
draft (maybe much less) to reach the shore. One one popular beach, I have only seen dingy's and some Wharrams actually reach the sand.
As previously mentioned, you can
anchor freely just about anywhere. You will see
dolphins, and if you do a little
diving there are a lot of
reefs and a few wrecks. All are freely available to you. The greatest challenge that I saw there was actually getting back onto shore.