It's been a several years since last visit to Cancun, but have fond memories. (Since we're getting older, we enjoy the relaxing atmosphere of Aruba.)
Night club wise in addition to Carlos & Charlies, is Senor Frogs, Hard Rock, Pat O'Briens (like in New Orleans w/dueling pianos). Probably alot more now. Also several booze cruises to Isla Mujares during the day and night. Definetely a younger crowd-loved going when I was in college/and in my 20's. Lots of hotels to choose from also. Have fun.