We always seem to have better dives from Cresent Bay North compared to the South side. A little deeper, always seems better sights. You can spend more than an hour at 30' with plenty to explore. Get a refill and do a second dive and see all new stuff. Swim the reef back in on your left and no safety stop required, you'll be 10' deep 30 yards from shore. Once you get a few dives in and are a bit familiar, try Deadman's Reef. From the North side, swim out until the house with the blue roof lines up between the big rocks and the stairs are at 30 degrees. Drop there to 40', reef runs pretty much WNW to ESE. 90' at the far side of the reef. It's a good kick to get out there, take your time, rest up on the surface, catch your breath then drop on down to a great dive spot.
You can hardly ever go wrong at Shaw's either, lots to see in in the crevice and trenches. Same thing, swim the reef back in on your left and your safety stop is covered.
I have a map for deadman's, I'll try to get it posted up but I only have it on my phone right now.
We go early morning, evening/night is good too. If conditions are going to be good that day, get there early to get a good parking spot.
Chris