I did look at Hotel Secreto during my scouting trip and it is beautiful. Lots of clean lines and modern style. It is a very small hotel so it wouldn't be able to accomodate many people. Also, although it does overlook the ocean, the hotel is mostly centered around the pool. I also read about the noice concerns on tripadviors, but I didn't really hear anything while I was there. Another boutique hotel idea in Isla Mujeres is Casa Sirena, which is located downtown, but has a beautiful rooftop patio. Happy planning!