The Utila Aggressor is a great one and a great value. You'll dive the best of Roatan and Utila.
When were you with her? I have heard conflicting reports as to whether they really move her much from week to week. It makes me think to ask that because I really enjoyed diving around Swan (aka Cisne), North of Roatan. When the BI Aggressor tried to get there, I was more than excited. Is the UAgg getting to Cayos Cochinos or Guanaja?
No, I have always stated that there are other great things in the Caribbean, it all depends on which of my posts you might read.
I like your top 3 list, too. If we went Top 5+ would add to it Northern Tobago and the Northern barrier islands of Grenada. Los Roques, West of Isla Margaritte Venezuala are difficult now that the Hughes ship is gone.
You really can't do better than Bonaire. As CCV is my favorite dive resort, Bonaire is my favorite dive island. Bonaire has great weather, viz, the drive-to shore dives, and the food can't be beat. Downside? No decent resort based shore dives remain and a pita to get there. The rest of the island's offerings more than makes up for it.
There's a lot of good stuff out there, most of it is hard to get to- that's why I am always talking Roatan. It's easy to fly in, fairly cheap in all respects, and the diving is still good- but don't wait too long.
That's why I keep banging the drum for the Bay Islands. It is developed enough right now to receive an influx of visitors, they will find it with enough developed infrastructure to make it an easy enough trip. Unfortunately, the speed of development and resultant siltation of the reefs make its days as one of the top Caribbean dive destinations numbered.
See it now before it's all gone. Like I say, you shoulda' seen Cayman in the 70's.
Same deal with the Bay islands.