The Mayan Riviera is like most coastal areas, each community has its own personality.
I think a great thing to do is sit down with your group ( you may already have done this of course ) ensure whom ever is in charge of finding your accomodations has an understanding of what is important to each person when it comes to where you should rent. The worst thing when travelling in a group is to not have everyone's input. That being said, as you are on the asking end you more than likely already have this information.
Puerto Morelos is approx 20 mins from Cancun International Airport, the beach is amazingly wide and normally you see people out front on Kite Boards. The town itself is on the small side, with a nice central park area which is just across from the beach. There are some nice restaurants in Puerto Morelos, that being said, unless the 8 of you really really like each others company you may find it is a bit on the slow side. We stayed for 4 days at Casita Blanca Condo's which were very nice with a restaurant and a really nice family managing. At the end of 4 nights I was really ready for 4 more nights in Playa del Carmen.
Playa del Carmen is so full of energy and life with an undercurrent of something a little bad ( in a good way that is ). We have been accomodated in more places than I can even remember over the years, but I would like to say I am a light sleeper who is up early looking for a great coffee while my husband and boys have a bit of a sleep in. I have stayed quite close to the noisy bar/disco area, but during a bit of a slower season and the noise of the bars and the boom boom of the beach bar near by was not a problem. Now this being said if I was off the beach and did not have the surf to mute or soften the noise it may have been an issue. I would stay on the beach in playa, but there are some areas on the avindas between 5th and the beach I would stay away from as the night life is nightly and it is lively. In Playa there are many neighborhoods within walking distance to Avinda Cinco, the beach, the ferries that are not noisy. Beautiful Beach with boats and people watching all day long.
Playa del Carmen has everything you would ever need for a two week vacation especially for first time visitors, two weeks will give you time to become comfortable enough to wander off the main area and experience the beautiful foods and neighborhoods around Playa.
Playacar is on the South End of Playa del Carmen, I have not had the pleasure of renting a villa for my own reasons. I have however stayed in a beachfront and the Holiday Inn Playacar on the 307. I enjoy having my beds made and not cooking when on vacation so we really try to stay in some type of Hotel/Resort/Inn etc. The Playacar area is so nice, it is a gated community with beautiful villas and some resorts within the community. It really is so close to everything that goes on in Playa del Carmen you would not have to worry about much. I think as I sit here that perhaps if I were to stay in Playacar in a Villa I would utilize the Taxi's alot more than normal as it still is a bit of a walk, depending on the type of day one has and or how the ladies are dressed for a night out, its a bit far for great shoes. There is a Chedrauli which we have often done our shopping at, its close to Playacar and there is Centro Maya right across the 307 from the Playacar entrance where one could easily get what ever you may need. Nice beaches.
Puerto Adventuras is to the South of Playacar approx 15 minutes away. Is a gated community as well. We actually found we really enjoyed Puerto Adventuras, but we opted to stay at an All Inclusive for a total relax and play volleyball kinda 4 days so we really did not get a chance to spend as much time in the Marina Area which I am assuming would have a really nice evening scene which both my husband and the two teen boys would have loved. We difinitely would love to try out Puerto Adventuras again. I am not a big fan of the Dolphin Swim thing personally, this Marina is a large Swim with the Dolphin Business. It was nice to sit and have the dolphins entertain you once their day was over and it was just them in their large pens. The marina has beautiful boats and alot of action during the day and evening. Some places have no beach only iron shore along the coast here, not all, but some.
Akumal is another 15 - 20 minutes to the South, the home of a great natural lagoon and the most beautiful snorkling bay. The community we did not spend alot of time in, but the boys really enjoyed Buena Vida and the Snorkling in a more natural setting with a smaller crowd of people than other similiar more advertised areas. There are many condominiums and private villas along the road in Akumal. A bit rockier beach area. I am not sure what the night life here would be, I am thinking perhaps a bit on the quiet side and the restaurants not sure as we usually stop at one place for our meals as the kids really like the area and the vibe at one place. Turtles are often seen in the bay.
Tulum is the farthest with the most beautiful beaches. A bit bohemium I would say and the night life is there, it changes nightly depending on whats happening in the area, Tulum town has shopping and great dining as well so a few options there. Beaches are WOW.
Okay now thats my take, and my take only. Perhaps not worded exactly as I would like it, but hopefully the words are helpful. I have arranged and travelled with a couple of groups small just couples and large and what we have considered and it has worked out well for us is try out two different locations condo/villa etc. You could do one week in Playacar and one week in Northern Playa just mix it up a bit, it keeps everything fresh and gives a better feel to where you are staying. There are some really helpful and good property management people who rent condos in each area if you ask on this site you are guaranteed great information. I have been helped so much by the people who are members here who work in Playa to provide Travel Agent/Management options.
We always pick Playa del Carmen for the end of our trips to Quintana Roo, we all love the vibe and we love the fact that we always feel safe. We have been travelling here for 10 years with our boys and they are now 16 and 14 they love Playa and so do their Mom and Dad. THis year we will be celebrating our first New Years Eve in Playa del Carmen.
Enjoy your research travelling with friends is always memorable and creates smiles for years to come.