In late November, we revisited the Chimney at Great Dog. The quantity and variety of fish was outstanding, and actually better than we had at The Indians. The one challenge is that there can be a lot of surge if there is any swell.
A couple first-time St John snorkel stops for me included Henley Cay (a tremendous amount of soft corals that were undamaged) and western point of Whistling Cay (was a bit underwhelming). It was a few days after the full moon, so the currents were particularly strong.
Monkey Point is always hit-or-miss for me. If there's been any surge, the visibility is greatly reduced (as it was on my Nov visit and I only saw 1 tarpon). Try to visit when the seas are calm and if you see pelicans diving you'll be greeted by massive baitfish schools and sometimes a dozen or more large tarpon.
.
