We're a family of 7 (kids 20, 20, 16, 14, 12) also and after much researching we reserved the Moon Palace.
I liked that the resort was a little higher quality than other all-inclusives and that they had private ceremony locations.
I also looked at the Hard-Rock but it was too much like a spring break resort. I'm sure it's fun but i ddnt want to equate my wedding with spring break! Maybe 15 years ago, yes but now not so much!
Good luck in your search!