I spend a fair amount of time in Mexico and prefer to stay at the W. It sounds like you prefer a St Regis type of property but the W is in the heart of Polanco in a neighborhood filled with restaurants and shops. Much more interesting than the area around the St Regis.
As to the 4 Points, next trip I am going to stay there as the neighborhood is certainly interesting and I have had good experience with international 4 Points.
I have tried them in Qingdao China and Bangkok and both were new construction and perfectly fine as opposed to some of the ones in the US which are just converted older hotels.