Of course key west and dry tortugas
are an option, as are any of the islands throughout the keys...some great sailing down that way. 3-4 days is pretty ambitious...a week, with a decent weather
window, yea, go for it.
Locally, Cabbage Key is a nice little stopover if you head out of the river there at Cape Coral
and N. through Pine Island Sound. Neat little island with a restaurant and a bit of history
. OR you could keep heading N. a bit up to Venice, and on to Sarasota
area and just explore around a bit. Some nice anchorages
and if you want a little more than a quiet night, Sarasota
sits right on the bay with a marina and/or anchorage right downtown.
One nice thing especially with limited time is that if you stay on this coast and head N. rather than crossing FL bay to the keys, the weather
won't play as much of a factor (i.e. won't get you stuck somewhere) as you can stay inside if necessary and still make way.
Have a nice ride,