Chichen Itza is a wonderful, must see, for anyone. The grounds are beautiful and there are enough history lessons there to cover days. BUT, the whole experience kind of gets ruined by the hawking vendors that are allowed on sight. HUNDREDS of them. Every step you take, someone is trying to sell you something. They should not be allowed there. Its awful.
We have been to Cozumel 8 times now and its a great port. Plenty of shopping, eating and watersports. The people there are pretty cool overall. We spent this trip at Jimmy Buffett's Margaritaville and enjoyed it tremendously. Great food, drinks and fun.