Cozumel/Playa Del Carmen x3, Fiji, Nusa Lembongan (Indonesia), Costa Rica (Pacific Side), Roatan, Channel Islands, Florida, and the Galapagos (liveaboard). We leave for a liveabaord in the Great Barrier Reef soon and have another liveaboard booked for Raja Ampat early next year.
The advanced certification has definitely been worth it in our opinion. Just so many places you can't go with just open water cert (particularly once you start investigating more remote places, wrecks, liveaboards, etc).
I'd definitely recommend Indonesia or Fiji if you haven't been before.
Next up on our list is Komodo Island (people rave about this place), Palau, and the Red Sea. So many places to go....