As far as USVI, I think St Croix bas long been considered the best diving there. We went once very long ago (stayed at Hotel Caravelle and dove with the op there.) Never had a great desire to go back, so I don’t have a good handle on resort and dive shop options there now. But probably your best bet for a dive trip. Not an AI, but reasonably convienient and lots to walk to.
We were in BVI in January. It’s beautiful, and a huge sailing destination, but not really a dive destination. Like dive if you’re going there anyway, but I wouldn’t plan a dedicated dive trip. The well known wreck of the Rhone is nice if you get out there, but in general I didn’t think the diving was anything special.
We were on the BVI Aggressor when they announced they were moving the boat to the Bahamas after March. The boat appeared to be generally under booked and just not viable to run there. It tends to be expensive to fly to Tortola which I’m sure doesn’t help. (You can do cheaper by flying to USVI and doing the ferry, but that has its own challenges.) It’s also not an inexpensive place if you want to stay on land, especially at a nicer resort. If you’re looking for anything like a dive resort with convenient diving and everything bundled with a resort I don’t think you’ll find that. You may find a few places that do meal packages and some on-site restaurants (including on the other islands.) But if you’re looking for a Sandals type place I don’t think they exist here. A lot of accommodations are on north side of Tortola while dive shops are on South side, The Aggressor didn’t go there I imagine there’s either not good diving or conditions aren’t suitable.