Cavewoman, very cool.
Which one are your favorites?
thx
That is a very tough question - they're all so different. So you've done Dos Ojos and El Eden (Ponderosa)? And you have some snorkelers with you.. I would probably then recommend Gran Cenote for your group, it is a stunning white cavern, and the snorkeling is really good too, so the whole group can go. Really pretty site, and good for everyone.
But if your other divers haven't done a cenote before, you should probably not start out there. Chac Mool and Dos Ojos are the usual starter dives. So if your friends are first-timers, Chac (since you haven't done it before) is probably a good choice. It has a nice halocline. No good for snorkelers, though.
As far as destinations for just the divers, that REALLY depends on the skill level. One of the "don't miss" dives is Angelita, which just a really surreal one-time experience. You all need to be Advanced minimum, and it's not the place to go if you're not all pretty good divers. You could combine Angelita with either Gran Cenote or Calavera, which is a very cool entrance (jumping in the hole from pretty far up, ladder back out) and is also gorgeous, with a really strong halocline.
My favorites for cavern tend to be really dark, really tight, and really silty and so aren't the place to go until you get a few more under your belt.
Wherever you end up, enjoy!