My husband and I, along with 50 family members, came to Cancun to be a part of my cousin's wedding. We stayed at the Riu Cancun, an all-inclusive resort, which is where all the guests stayed.
Her wedding was to be on the beach oh a Friday afternoon, but an hour before the wedding, a storm rolled in and the ceremony had to take place in the resort's outdoor covered patio. The ceremony was nice, but the resort didn't seem at all prepared for the scenario of rain and was a bit unorganized trying to set up on the patio.
After the ceremony, pictures were taken on the grounds, and eventually everyone ended up in the swim-up bar in their wedding attire... and it made for a great pic to end the afternoon before dinner.
The resort itself is okay, but my husband and I did venture out and do other things, and there are plenty of things to do if you want more than hanging around the pool.
Do plan on reserving room on a tour when you first get to Cancun, because a lot of the tours fill up and certain days of the week they don't do tours.