Cozumel Palace
Simply, Cozumel Palace, is touted as one of the nicest hotels on Cozumel. It's not a "cheap" hotel, and the service, food, and accommodations reflect that. We had a Concierge Level room, which gave us a pillow menu, top floor ocean view, and some other niceties. The Cozumel Palace has multiple restaurants, bars, and a buffet. You can eat and drink to your heart's content, and the food was great -- especially the afternoon guacamole they put out daily. The staff is top notch, and takes care of everything. They had rental cars on site, which made taking a day to drive around very easy.
The dive operation on site was professional and accommodating to a diverse group. We chose the "slow boats" on purpose because they had shade and a head (bathroom). We didn't do any shore diving during our stay, as the conditions didn't allow it -- the red flag was up the whole week. We dove the wreck (C-53) one day, and the rest of the time along the walls and other popular sites. My favorite was Palancar Bricks as we saw a couple nurse sharks snoozing under a ledge and a couple turtles. We did one night dive at Paradise Reef, and found a couple octopus and a lot of lobsters.
Overall, we would definitely stay at the Cozumel Palace again! It's centrally located, making it easy to walk to town to visit bars, restaurants, shops, etc.