Sounds great & Playa Del Carmen is a great place & very safe. Lovely atmosphere down the main drag (5th Avenue), lots of bars & shops & music aplenty.
In the past we've stayed @ Barcelo Maya Beach Resort, Sandos Caracol Beach Resort & Spa & the Rui Tequila @ Playacar(gated community of hotels within walking distance of Playa Del Carmen. All excellent Hotels with great beaches, great food & lots of entertainment.
We visited Xcaret, Tulum, Coba, Swimming with Dolphins in Cancun aquarium, there is plenty to see & do!
If it has any lagoons make sure you take mossie repellant though.
Have a great time
Grant