I don't think an ideal match for the criteria will be found, but there are some reasonable compromises. Sounds like we're looking at Southeastern Florida, the Bahamas and the Caribbean region. Okay, if we put aside Cozumel and shore diving as desirable, and go with land-based (unless you guys are interested in live-aboard diving?), mainstream options are...
1.) Key Largo in the Florida Keys - such as
my old 2013 trip with Rainbow Reef Dive Center. Viz. wasn't as good as these other options, but there was the option for deep wrecks where Goliath grouper might be seen. I found it pretty fish, and it's quite aways from the places you've already been. Land-based entertainments on the mainland may be a draw.
2.) Roatan - a different part from where you went before? Turquoise Bay Resort seems popular for A.I. package deals with plenty of good diving.
3.) Belize - Ambergris Caye diving doesn't have the rep. for the quality of diving the outer atolls (I did the latter via live-aboard), but should be cheaper than, say, Turneffe Island Resort.
4.)
Curacao - while shore diving is part of the charm, you can have a good time boat diving.
5.) Perhaps the
Juliet live-aboard hitting the Bahamas would appeal?
6.) The Caymans don't have a rep. for being cheap, but perhaps a sale at Cayman Brac Beach Resort?
Sunset House in Grand Cayman has had some deals in the past.
7.)
St. Croix didn't strike me as a 'cheap' destination, but it's got its own charm. I like the diving in Belize's outer atolls and Little Cayman better, but when topside is factored in, it's a cool, laid back place.
Richard.