This is tough to answer because there are different factors in play.
1.) Your profile indicates under 25 dives, and you mentioned being OW certified. Didn't mention Advanced OW or Nitrox certification. I'm guessing you maybe haven't traveled far outside the U.S. much before?
If all this is true, I think the Galapagos and Socorros are probably out for now. Not sure how keen you'd be on far distant locations like Bali and Fiji, mentioned by others and outside my experience.
2.) Exotic locales in the Caribbean and Bahamas region (other than Tiger Beach, which I suspect you're not ready for) may not be your best best for 'big stuff.' You might be much better served in that respect closer to home, hitting North Carolina for the sand tiger sharks and/or Jupiter, FL for Goliath grouper and some reef sharks (at the right time of year maybe lemon sharks, or later in your diving when you're ready for it, if you don't have philosophical objections, maybe shark feed diving where the shark menu goes way up).
1.) North Carolina - Morehead City, NC August 2015 -
http://www.scubaboard.com/forums/no...us-dive-center-aug-9-13-2015-trip-report.html
2.) Jupiter, FL - Jupiter 2014 -
http://www.scubaboard.com/forums/florida-diving/491927-jupiter-trip-report-9-7-14-9-11-14-a.html
3.) Shark Feed Diving out of Jupiter, FL - Emerald Charters Trip Report 2017 -
Emerald Dive Charters Trip Report
Now, if a few green and hawksbill sea turtles, some tarpon, Caribbean reef and nurse sharks, a big green moray eel, maybe an adult barracuda, and a black or Nassau grouper or similar fit the bill for your 'big stuff' list, then those 'exotic' options open up a good deal. The Cayman Islands, Belize, Turks & Caicos, and don't forget Key Largo.
In fact, while it may not seem so exotic, Key Largo offers a nice mix of deep wreck diving (where you may see a Goliath grouper) and shallow reef diving over a hard bottom.
Key Largo with Rainbow Reef Dive Center 2013 -
http://www.scubaboard.com/forums/fl...iving-key-largo-rainbow-reef-dive-center.html
And when you're ready for cold water ocean diving, the sea lions, harbor seals, bat rays and giant sea bass out of California are fun. Truth Aquatics Vision Trip Aug. 2016 -
Truth Aquatics Aug. 2016 Trip Report - California
With all the uncertainty about getting into countries and quarantining, etc..., my suggestion is get nitrox and preferably AOW certified (for deep wreck diving), hit Key Largo, do 2-tank morning dive trips, then hit the road with your wife and do local excursions, or maybe a longer drive to the mainland for Zoo Miami, Jungle Island (Miami area) or other activities. Ever been on an Everglades airboat? If you don't have philosophical objections (the marine mammal exploitation thing), dolphin excursions can be sweet.
Richard.