I live up north from you a bit and ride A1A pretty much every weekend, often starting in Pompano or Boca Raton, heading North, as it's a less-trafficky, more enjoyable ride that direction. I'm 52 and ride with friends, not really a group, that are about your age, all pretty much new to cycling. We usually do a longer ride on Saturday (50+) and a shorter one on Sunday (30-40), leaving around 6AM (too hot otherwise) with often a breakfast stop at Luna Rosa's in Delray. If you'd like to join us, or I'd take the time to meet up with you and just ride one weekend, send me a pm. Also, there are so many cycling clubs in the area, and they break their riders into groups based on mph. I'd check with a local bike shop (i don't know the ones in Ft. Lauderdale). The Boca Raton Bicycle Club is huge and has rides all week and a website calendar. I haven't gotten together with them yet, but have met members, who all seem enthusiastic and really nice. Welcome to Florida!
2013 Kirk Frameworks JK Special/Selle Anatomica
2012 Gunnar Sport/Brooks B17
2001 Calfee Tetra Pro/Selle Anatomica
1984 Raleigh Sport/Brooks B66