We got married in Tulum last year, we had a civil ceremony in the morning and then a cosmic ceremony with Maria and Charlie at sunset. It was amazing and the favourite part of the day for most of our guests, I highly recommend them if you want something different!
I would go to Tulum as there are so many beautiful parts of the beach. In front of El Pez there is a big rock where the beach has the sea on both sides, that is where we had ours. Or head into the Sian Kaan Biosphere if you want it more deserted.
When are you having the ceremony? My husband is a Videographer but we won't be back in Playa until after the 19th November.
There is a good Florist on 30th opposite mega (Floreria Sac-Nah I think). I used Adrain http://stylingtriorivieramaya.com/
and Christian firstname.lastname@example.org for Hair and Make up and they were great.