I am a little suprised about some of the comments here about Cozumel diving. Although I have not been there for about two years, we did dive there twice a year for 4 or 5 years before that. We used one of the largest dive operators and dove on the "fast boats". They would take a maximum of 6-8 divers and the divemaster and Captain and would travel out farther. As a result "so many divers in the water at the same time it was like a parade" was never our experience. Many of the operators offered the same service. As far as the quality of the service we received on the boats, it was generally better than we received in AC. These trips were $60-65 a person for two tank dives and nearly always involved a longer trip than we experienced at AC. They seldom brought us back between dives, too far. I checked the website and that price appears to be current although there are always discount prices for packages. I also have no idea what may happen to the price after they rebuild from the hurricane. Talk about hidden costs!
We have also been diving in Mahahual Mexico, Guanaha Honduras and Little Corn, Nicaraga and although remote they were all less than $60 for a two tank dive. The dive operators in Bonaire are approximately the same price $60-65. The Cayman Islands are more expensive $75 to 85. I think that you have to consider that these locations are your competition for someone trying to book a dive trip from the states. I would agree that a 10% increase would probably not deter many travelers. Raising your rates more than that, I think, would affect decisions. Especially for people booking for a dive club or a group. You also have the disadvantage of a 9% tax and sometimes a park fee on top of your charges.
Cozumel does have some advantages for their operators. There seems to be an excess of divemasters. We dove with some excellent guides, with years of experience, who could only get one or two trips a week during the off season. That may have been part of the reason for great attention. Those who develop good reputations or are requested by the divers, get the work. I would also assume that fuel is less expensive. I guess there are no easy decisions for AC dive operators but I hope that my perceptions will add a little to your insights.