My wife and I plan on a dive vacation, minimum of 2 weeks and are currently considering Cayman Aggressor and Cayman Brac.
When you say 'Aggressor and Cayman Brac,' do you mean a 7-day
Cayman Aggressor IV liveaboard trip + a land-based Cayman Brac trip (e.g.: Cayman Brac Beach Resort)?
My trip reports on them are rather old, but I've done some of what you're looking at, if you want to see how that went.
Sun Dancer 2 (later renamed
Belize Aggressor IV) (Belize) May 2015 -
http://www.scubaboard.com/forums/li...ving-belize-via-sun-dancer-2-may-2nd-9th.html
Dive Trip to the Blue Hole & Visit to Half Moon Caye -
http://www.scubaboard.com/forums/belize/506647-some-blue-hole-impressions.html
Cayman Aggressor IV May 2016 -
Trip Report - Cayman Aggressor IV Trip May 2016
Turks & Caicos Aggressor II Report Apr. 2018 -
Trip Report - Turks & Caicos Aggressor II 4/21-4/28 Trip Report
Turks & Caicos Research Notes -
Turks & Caicos Research Notes
Between retirement, less money, high inflation, parenting and wife going back to work, when I get wet lately it's because it's raining, so hopefully my commentary won't be too dated. Some thoughts on your thread:
1.) Some people prefer land-based when it hits similar sites, preferring liveaboards where they offer access to places the land op.s don't. For that reason, some are less enthused with the Caymans or Roatan as liveaboard destinations.
2.) With the Caymans, the liveaboard might not make the crossing, but if you're spending a week on Cayman Brac anyway... Still, Grand Cayman is an interesting place, and if I were going to 'stuck' diving it for a week, unless traveling solo it might be fun to do land-based and explore topside.
3.) I preferred the liveaboard diving out of Belize and the Caymans over Turks & Caicos (which is really just Caicos); T&C does benefit from live board diving due to long boat rides out, and I enjoyed the trip, but it averages deeper wall so there's not as much colorful scenery in the well sun-lit shallows. T&C has a rep. for being expensive topside; liveaboard is the way to do it, from my perspective.
4.) The Blue Hole dive out of Belize is okay, but short and I didn't find it that striking. Glad I did it for the bucket list. Wouldn't go out of my way to do it again, most likely.
5.) I wonder if a week on Little Cayman for what's at times alleged to be the 'best diving in the Caribbean,' coupled with a week in Grand Cayman for the combo. of good diving + some topside entertainments, might be good for you? One fly in that ointment - if you are a die hard 5-dive/day 'eat/sleep/dive - if I'm conscious I should be chewing or wet' dive tourist, land-based may not satisfy you. IIRC, Little Cayman Beach Resort is mostly a 3 dive/day place, plus some night dives offered.
6.) Another option is a week on a Belize liveaboard, followed by a land-based week. You might do a forum search on a place called Placencia if you would like to get in some land tours - I haven't been, but it's gotten discussed on ScubaBoard before.
Best wishes for your trip.