Looks like a fabulous plan Mick! Awesome. Heading to AK this Jan. Will give you the scoop!
Yes, the catamaran should be leaving out of Ft. Myers Beach area (not far south from Cape Coral, Mick).
Things to do on the gulf coast... Well Sarasota is nice, as is the Fort Myers Beach area. I actually prefer Ft. Myers Beach to the Sanibel and Captiva Islands. The Islands are ok to visit, but honestly kind of boring.
When you drive back to Miami you'll take Alligator Alley. Leave time for a nice drive. There is so much to see (and 'gators are only part of it) along this portion of 75.
Oh! There (used to be anyway) is a sunset cruise out of Ft. Myers Beach. It's called Red Sails in the Sunset. It's really nice and a cool way to watch the sun go down.
You might want to contact the chambers of commerce for each area you are interested in on the Gulf Coast. They have loads of info, and may even mail it overseas to you. Buy a good guide book of Florida (or two). They are really useful for so many things.
ive just got my friends villa website address and looked at the photos(not seen for a while) and its absolutely amazing, stunning in fact. one of the best looking villas ive ever seen. what they have done with the pool screen is real cool too. they have opened up the view from the huge lanai over the infinity edge pool out to the lake and beyond so there are no bars, just mesh so the sunset view is superb. from the reviews there is stuff to do, beach isnt far ft myers looks like its just up the road a bit. so im thinking maybe i need to think about staying there for the amount of days we would be there, looks like being 5 nights. so i think this could be a nice place to do a bit of shopping as there are outlets there, karting, and a water park all close by and some days at the beach