assuming you're talking of all inclusive resorts..
I've found that there are definitely "levels" of all inclusive resorts..
I have stayed at the Blue Bay Esmerelda and the Bahia Principe Tulum.. both were very nice ... grounds and pool were great.. drinks were so-so (not top shelf) and the food was just okay.. Great at first but after a few days it became kind of tiresome...
Beach at the esmerelda was not that great (lots of seaweed) so if beach is important i'd stay away from blue bay. Beach at bahia principe was great.
For my wedding we are having it at the barcelo maya palace. This is allegedly a much higher end property based on reviews i've read on destination wedding forums etc
Actually one thing I've noted with mayan riviera properties is that many hotels have more than one hotel on the property..
For instance the barcelo maya palace where I'm going also has the barcelo maya tropical, barcelo maya caribe, barcelo maya colonial, and barcelo maya beach on the same property. However guests of palace, get better restaurants and top shelf booze.
Basically you can't go by a name alone.. there are good, better, and best of each resort chain.. not all Riu are the same, not all Barcelo are the same, etc.
IF booze is important also note what type the resort provides. look for resorts that offer top shelf booze otherwise you will be charged for name brand alcohols (or be forced to drink crappy booze)
all in all you can't really go wrong but for the money I'd def bump it up to a higher star rating to get better booze, better food, better rooms, etc
Other advice - don't book a shuttle when you book your trip.. book it after at cancunshuttle.com .. example
orbitz wanted $80pp for shared shuttle
travelocity wanted $42 pp
we found private transport for 2 on cancunshuttle.com for $115 (round trip) and $130 for 4 people (van). Private transport is much quicker than stopping at multiple resorts and it came out cheaper than the group shuttles (especially with 4 people)
tours -- if you do tours the resort will book you in things that include transportation. Depending on your location in the mayan riviera, it may be cheaper to take a taxi.
xplor with transport = $116 pp
say 4 people so that's $464
now if you do w/o transport
taxi each way $15
admission $89 x 4
total = $386
of course it depends on where you are vs taxi costs,etc but generally the more people going on the tour, if they can fit in a taxi you will save some $ doing it yourself..
tipping: even at all inclusive where tips are supposed to be included, you will find you want to tip bartenders, waitstaff, maids, bellboys, etc. They work for so little and really something like a $1 goes so far. So we bring lots of $1's and $5's with us because it's tough to get small denomination of US or pesos once in mexico. Maybe for a week we give out $50 in tips. Outside of the resort people expect tips (tour operators, taxi drivers). a little goes a long way here and they are very nice and appreciative.
if you leave the resort, don't drink the water or drink anything with ice cubes in it. Stick to bottled soda/beer/water only. the water isn't "bad" .. it's just different from what your body is used to.
and lastly, pack Immodium!
OK so hopefully you've found something useful out of that