Nice website.
I dove Grand Cayman in January, all on the southeast side due to weather. It was incredible! Lots of fantastic walls, canyons, coral formations, and a lot of fish/critters. We swam thru schools of tarpon and cuda, silversides, and on one dive (Grouper Grotto) had 12 eagle rays zoom right over our heads as we were checking out the canyons.
We hired a boat from Red Sail one day for snorkeling, but like you weren't all that impressed with the north side although the weather prevented us from going outside the barrier reef.
On one snorkeling trip inside the barrier reef just west of the Lighthouse restaurant I had the pleasure of swimming 30 feet away from an eagle ray. The coral inside the reef is often thick clusters with sand chutes between them. The eagle ray and I swam up a chute right next to each other and then he realized it was a deadend. So we both turned around and swam back out.
I dove Cozumel about 3 years ago, and your pictures were great. They reminded me about how clear the water was there. Too bad you didn't have more time there because there's no shortage of fantastic dives sites there.