I would book it myself and use
http://www.usa-transfers.com for my roundtrip transfer. They are great, on time every time, and waiting for you when you land at Cancun airport. Its a private transfer, so no waiting for other people.
El Dorado Royale is very nice
Secrets Maroma..... is incredibly great with a great beach too, if the saragassum is not so bad, but its been terrible this whole year.
Rosewood Mayakoba and Banyan Tree Mayakoba......if money doesn't matter
A little less money but a great place is Excellence Riviera Cancun. Not Cancun, between Cancun and Playa.
Of course there are tons of great places, but the extra money will get you adults only and more peace and quiet.