Ajijic is a lovely spot to see the lake and mountains in their entirety. Not only do you get the gorgeous food but, you can shop as eat delicious snacks/foods.
Book a boat tour of the lovely Lago Chapala! Whilst you cannot swim in this lovely lake, it has breathtaking sites.
Monte Coxala Spa de Altura
300 Rafael Osuna, San Juan Cosalá, Jal. 45820, Mexico
This relaxing spa sits just 30 minutes down the mountain from Quinta San Carlos. If you love the idea of a massage in the mountains this is perfect for you. They offer day passes as well as various spa packages.