Just my two cents...
I've been to St. Lucia, Turks and Caicos Islands, and Freeport/Lucaya in the Bahamas. Freeport is good for families. St. Lucia does have some family friendly resorts, but it's a lot quieter and laid back. The largest resorts in the Turks and Caicos Islands only have about 100 rooms, so it's perfect for a couple's adult vacation, not a family one. I've been there several times.
Nowadays, all-inclusive only works if you don't mind mediocre food and limited low-end alcohol. I did the all-inclusive deal back when they included alcohol, even the top-shelf stuff. I don't think they do that anymore unless you pay a substantial premium. They also surcharged for the higher end meals.
You'll find good deals everywhere right now, but the Bahamas is probably the most economical and the closest. Many of the places I visited in Freeport were carrying counterfeit Cuban cigars, even the high end bars and restaurants. I didn't have that problem with the more exotic destinations.