I visited Chichen Itza in 2003 with my family, when you could still climb on and in the El Castillo pyramid. It's very enjoyable and iconic, I guess, but it is  not my favorite ancient Maya site.  I've visited a couple dozen different of the ancient cities around Mexico and Guatemala so far. While Chichen Itza is large and there is a lot to see, especially the impressive Ball Court, I prefer several others ahead of it.  I think my main complaints against CI are that it is over-touristed and has relatively little historic "atmosphere". My feelings are also probably tainted a little bit by the fact that we hired one of the official guides there for our  tour, and he was not very good. It bothers me that it was selected as the representative "new 7 wonders" site, seemingly mostly because tourists can hit it as a day trip from Cancun. Sites I'd recommend over CI include definitely Tikal, Calakmul, Palenque,  even nearby Uxmal, and probably a couple others.  It is worth it as an easy trip from Cancun, but if it gets you excited about the ancient Maya, recognize that there are even more impressive places, where you can have  a lot more fun climbing on the major pyramids still.