Again, we have plenty of the same shit here, earlier, more original and prettier. Take some time for a trip to Paris if you will and walk the streets, then you realize. Walk rue du Quatre Septembre, boulevard des Italiens, the entire surroundings of Opéra Garnier, some residential streets of the 16th arrondissement, and more, you'll see that we have lots of things more remarkable than this building in New York.
What do you think? It's no accident if they decided to eventually demolish it. They know about what they are doing.
So it's no use keeping it, friend. Let them free themselves and build something much taller to host more people right there. They will build something very good on this spot. How could you even be doubtful?
If you want some real quality Neo-Classical crap that must roughly be from the same era, see the Book tower they're refurbishing in Detroit. I'm usually against neo-stuff and pastiches cause it's backwards, but that one is an exception. It looks like an absolute neo-Roman dream. Sometimes, even always, some exceptions occur like that one. I bet even the hard-line French modernists would bow to that one in Detroit, but not to this one on the 5th avenue. It's nothing so outstanding.
So you'll have to mourn it until you make Paris your own (which is nothing impossible).