Honestly, I wish to heck I'd had more time to research my first cruise back in June (or my upcoming
DCL which will probably be my last), because both do Nassau; and Cozumel, while still touristy, sounds like a MUCH better time. Lots of family friendly all inclusive day resorts, a reasonably consistent taxi system, tons of snorkeling spots, good food, and seemingly no state department warnings or *exceptionally* obnoxious vendors like Nassau. There are also three different cruise ship piers and I assume that spreads things out a bit.
This is just what I have read.