Alternative all-inclusives to Palace group in Cancun?

What are good alternatives to the Palace group of all-inclusives in and
around Cancun (Aventura Spa, Moon, Sun, etc.)? They are currently
running a promotion of unlimited tours to Tolun, snorkeling on a small
island, Chicenitza (sic?), which adds to their attraction, but from my
location they are a little pricey, though not forbidding.

Just want to make sure that we are not missing a better value.

Our interests are the usual: a bit of snorkeling, touring ruins, nature
parks, a bit of "beached whale" non-activity, a room comfortable for
three adults, Carnival cruise ship (or better) level dining, etc.
George Litwinski

"It's good to want things."

S. Barr (philosopher, poet, humorist, chemist, Visual Basic.Net
programmer)