We have considered a live aboard but just don't know if we are that hard core. 3 maybe 4 dives a day is our max. We love diving but in the end it is also a vacation and we don't want to feel we have to go on a dive.
While many liveaboards offer up 5 dives a day, some are less, depends on the location and clientele. In any event it's rare for people to do all of them. Some boats give out a variety of humorous prizes at the end of a trip, often one will be a certificate to anyone who did all the dives, and that's typically 1-2 people. Night dives (actually all dives) tend to get more sparsely attended as a trip goes on, and many people simply aren't into night diving at all. People sit out all the time to rest their ears, get more hammock time, just don't feel like it, whatever. I've seen people do the first 2-3 dives each day then dive into a bottle of wine. I average something under 4, and the only thing that makes me feel I "have" to go is if the diving is really outstanding and I don't want to miss something. So if you do 3-4 a day you're plenty hard-core enough. And there's a chance you'll find you want to do a bit more than you usually do, simply because it's so convenient compared to most anything land-based.
Personally, I really like combining a liveaboard with some time on land to get the best of both. Plus it's so much nicer to get off the boat and go to a resort, than slog off to some airport early in the morning. Also easier to deal with packing.
I think if you haven't done it, someplace in the Indo-Pacific is a great idea for a special trip as the diving is generally so much better and different than Caribbean. However, if you don't want currents or muck, that's somewhat limiting as so many places in the region have plenty of one or both. (If you haven't done any good muck diving, which you haven't if you've stuck to the Caribbean so far, you may find you like it if you try it. There are places that have a mix so you wouldn't only be doing muck diving. The thing about completely avoiding "muck" and currents is, yes you will be able to to easily take pics of coral and the usual type of stuff that lives on a quiet reef. But you will never get to see - or take pics of - all the cool stuff that doesn't.)