I have never been to Abaco but I think I must know every web site there is that has some bit of info. Plus I follow this message board, looking for info.
So that said, I think that G Guana Cay and Green T Cay may be good choices for your snorkeling adventure.
From what I read on internet and with the numerous calls that I've made to islanders, the possibilities are ENDLESS. You'll find what your looking for and even more.
Down the message board aways, there is a complaint about how GGC is not so great for snorkeling, in fact poor.
I have reservations at Abaco Beach Resort for July 9 arrival. I looked at many lodging possibilities, thinking of the snorkeling also. I was very interested in Guana Seaside Village, Bluff House and better yet a nice little villa on GGC but my wife likes too many creature comforts. I could sleep on the beach.
ENJOY!!!

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