Ramon's. Having clarified your needs, I would agree with PSUhorty. It has all the services you mentioned including about a 4 minute walk along the beach to town. On a realistic note, they are overpriced for what you get. But, they offer everything you need and I can't think of a better place that meets all of your needs. Their dive/water sport shop is probably the 2nd best in terms of professional staff and quality of boats/equipment out of, I'm guessing, 40-50 plus establishments on AC. They have a quant little pool and bar, and the restaurant area is laid out nicely looking to the beach, and a staff more than ready to plan your side trips. As a side note, they are about 300 yards from the airport (noise of planes not really an issue). Ramon's also backs onto the main street heading South - Coconut Drive. This can be noisy at times but, their property is deep enough that I would be inclined to request a grouping of units toward the front/beach.
By the way, the plane from BZE to San Pedro Airstrip, whether Tropic Air or Maya Island Air, will be a Cessna Caravan which holds 13 passengers including one in the right hand seat plus the captain(for a total of 14). So, you may be able to get a special charter price from them for the whole plane, even though you will probably have it all to yourselves anyway. I personally prefer Tropic Air. They are very good at returning emails and their terminal on AC has AC...for when you are waiting to leave...