Okay, here is the scoop....
If you looking for an All Inclusive (perhps adults only

), and a more lively atmosphere... then look into resorts on the Riviera Maya, the Playa Del Carmen area... You can simply ferry over to Cozumel, a matter of minutes, if you are wanting to go there for diving, etc... There is Playa Del Carmen and the beach clubs for partying on the weekends, if that might interest you. There are the ancient Mayan Ruins... Snorkeling if you would be interested in going down to Akumal, the cenotes, etc... etc... etc...
I would love to go to Secrets Maroma Beach - undoubtedly the most beautiful beach in the area. Uncrowded, only a couple of other resorts around. Of course, which resort might also depend on how much you are willing to spend. There are many All inclusive resorts in the area to choose from. (so many it might take a while to look into them and decide which one.)
Go to tripadvisor, and compare both areas.
I would imagine that they each have their own totally different atmosphere/vibe.
Both would be wonderful destinations with wonderful beaches!
You didn't mention diving... (sounds like nice all inclusive adult only romance is your thing....) but if diving is your purpose, then be sure to consider islands, such as Grand Cayman that offer excellent diving with uber clear waters and good dive opportunities.
PS: I think that perhaps the safety warnings would be more for border towns and inland Mexico.
I don't think that it is, yet, such a major concern in the Cancun/Playa area.