I haven't done the Caribbean, but it's on the list!
Sadly because of USA politics ships that sail/to from there can't stop off in Cuba. I see Ambassador do a no fly from the UK that avoids the USA for a round trip the includes Cuba and Jamaica but I'd never use them, they're shite.
Miami is the biggest and busiest cruise port in the world. There's bound to be a cruise line that would fit your budget, whatever it is.
For me it would be pick the places you'd like to visit and find an itinerary that fits as many in as you can.
Mrs Jackie and I always get a balcony cabin, although we upgraded to a suite on our most recent trip. We've decided the extra cost isn't really worth it.
Our next trip will be the Far East next year during the Japanese Blossom Season. Guess who picked that one? At the moment we can't decide on a lap of Japan or a trip to or from Singapore, both about 20 nights including flying time.
I'm not sure if
@egb_hibs has caught the drift about relaxed cruising

Sea days are when you really really relax and take in the full benefits of sailing in a super hotel.
And I'm not sure about expert status! We've done almost 100 nights on board. There were a couple of couples on my last cruise who'd done over 100 cruises!