My wife and I stayed at the Majestic Elegance for a family member's destination wedding. If you want some place to relax, I would not recommend it. Even if you wanted someplace rowdy, I wouldn't recommend it. There were never enough towels. We ordered room service once and it never came. The room smelled of mildew. The food was mediocre (though I suspect this is pretty much always the case at all-inclusives). YMMV.
In general, I think all-inclusives tend to be rowdy, because most people choose all-inclusives to save on alcohol costs. The more people drink, the rowdier it will be. So, if you're most interested in relaxing, I personally would stay away from all-inclusives. On the airport shuttle, we did stop by the Iberostar, and from the outside, it looked fantastic. Perhaps someone else had a more positive experience elsewhere and can help you. But from my experience, the Majestic will not provide you with what you're after.