I haven't stayed at the Hyatt, but stayed at a Hilton far north of the city.

I can say, staying near Centro is the best for long term. Lots of places to eat and check out in the center of town. The airport is far south of the city and you only have one transportation choice from the airport to the hotel, and that is a authorized airport taxi.

That airport is under the control of the Mexican military and ride sharing apps are prohibited, even though some alleged Uber drivers show up and act like taxis to get cash and don't use the app. I say all that to say, use the taxi if you go to Merida.

I was there for almost two weeks in December over Christmas and it was hot and humid STILL😀

But, if I had to do it over, I would definitely stay inside Centro because it's a pain getting local buses or collectivos (small vans that don't move until full).

I flew there from Mexico City, so you'll probably have a layover somewhere to make it to Merida.