Post-cruise, I dropped off my niece at the FLL airport, rented a car, drove to Key West, and was back at the airport to catch a late evening flight.
Even without going all the way to Key West, the water in the Keys would be worth getting away from the Florida Atlantic Coast.
If I had a few days (and some $$), I would head to a Key West, do a day trip to Dry Tortugas National Park (ferry or float plane - I did the latter), then back to FLL.
Last year, we stayed at Ft Lauderdale Beach; there was nothing particularly pretty nor charming about it or the area. Same could be said for Miami. (I have enjoyed vacations to lots of places. Actually, it is FL in general that holds little interest for me - other than as starting ports to other places. And WDW. The Gulf beaches are more appealing). South Beach in Miami looks to be prettier than Ft Lauderdale.
I would also consider Everglades (2 hr away) and Biscayne National Parks (just South of Miami).