Most of the Yucatan peninsula isn't crowded or touristy, but I especially enjoyed eastern Campeche and southwestern Yucatan. It was noticeably drier than further south, but it was still green and lovely. The stars were wonderful and it smelled so good there.
In Campeche we saw lots of Mennonites who have large corn fields around Dzibalchen. In the towns you wouldn't see taxis, ever, but there were plenty of pedicabs which work great since the entire area is flat. We stayed in a peaceful hotel just south of Santa Elena for two nights that included a great breakfast (chaya empanadas!) and a sandbag structure. I loved everything about the trip, but this area was my favorite.