Snorkeling with Alfonso Graniel, L'il Alfonse, would be great and you could hire him just for your group. Alfonse is wonderful with animals and people and he is reasonably priced; he will pick you up at your dock. You can call him once you reach the island, 614-5450, 226-3537. He is under the "Goods and Services" drop down menu above.
If you are into fishing, the Guerrero brothers, Severo & Ramon are excellent and fun and do a great beach picnic with your fish, 226-2324, 226-2325.
Happy time there again and enjoy your guide role!