I posted a review and photos of the Sea Breeze Apartments on my blog. The Sea Breeze is located in Pos Chikito, a few blocks from the Mangel Halto where all that good snorkeling can be had.
There are studio and one bedroom apartments here for short and longer term stays. There is a small pool, wood-fired BBQ, and a nice palapa for casual gatherings. It's a great place to stay if you have a medium sized group and everyone can have their own rooms without being on top of each other.
It is located in a regular neighborhood as opposed to among all the hotels. Marina Pirata is close by and it's only a short drive to Flying Fishbone and Old Man and the Sea. You won't experience much hustle and bustle here, which may be just what you're looking for.