I have no real answers, but looking for recommendations for Antigua, too. My husband and I went on a day of diving there back in 2013 while on a cruise and used Indigo Divers. No complaints - I got really seasick and had to cancel the 2nd dive - so they dropped us off at the harbor so I didn't have to sit on the boat while the others went diving.
We are traveling there on a family trip (16 people!!) in July. 4 of us are certified divers and 2 others have done "discover scuba" classes and might want to go. We are in a villa at the Blue Waters Resort and Spa up north, about 15'ish minutes from the airport (I think). I've heard good things about DiveCarib and Antigua Scuba School, in addition to Indigo Divers.
FYI - I'm only going to make plans for my husband and myself - the other divers can come along if they choose, but I'm not planning for them. We just want a very good, highly competent dive shop to work with. Anyone have suggestions?