Mahahual changed forever when the cruise-ship dock was completed, and it grows larger every year. Despite the (literally) boatloads of tourists, there's a lovely, relaxed, Caribbean vibe that you won't find further north, and once the passengers have returned to their ships, a quiet calm settles over the town. Mahahual is the only spot in the Costa Maya that's large enough to support a diversity of sleeping and eating options, while still being right on the beach.
New restaurants and bars are cropping up on the north side of town, a residential area known as casitas that's home to both locals and foreigners. Or go south toward Xcalak and you'll have no problem finding your own private beach with sugar-white sand.
There's great diving and snorkeling in Mahahual, and just enough nightlife along the beachfront malecón (waterfront promenade) to keep you entertained.