If I had to choose, I would go a few miles north to Sanibel Island. Even though I'm older, I associate Marco as more for seniors and more for homeowners. Sanibel is more for a younger crowd, resorts, and you have Ft. Myers nearby if you want more to do.
https://www.google.com/maps/place/Sa...!4d-82.1115119
https://sanibel-captiva.org/sanibel-...tels-specials/