We stayed at the AI resort, Villas Jibacoa, in 2011. There was an onsite dive op. We did many dives with them, including my 3 children to get OW certified. For all of the dives, 6 of us (2 DM, one stay on peddle boat) went out on two peddle boats. There were actually enough dive sites we could get to on those peddle boats.
The dives were better than those in Varadero. I dove in Varadero in 2003, and we went there again earlier this year.
At Jibacoa, I did also go next door to Breezes to ask about their dive op. They had a boat, but could not take my children while they were completing the OW certification. I could sign up with them myself as I was certified, but they could not guarantee me space, as the priority is for their resort guests. So I didn't sign up to go out with them. As such, I cannot comment on dive sites you can get to by boat. But those sites we peddled to, were quite decent. Those sites would also not get a lot of traffic. There are only 2 AI resorts there.
We would not go back to Villas Jibocoa though. The accommodation in villa rooms were ok, facility ok. It was a 3* but in Cuba that means the food is not very good. I did not see them clean or change the placemats in the dining room for the entire week. In fact, my middle son and I got sick for 2 days close to the end. The Breezes is apparently much better, but as a 4* resort would be more expensive. If they still have a dive op, I'd give them a try.