JFK T4 seems like it would be a pretty ideal place for one since there are a bunch of international airlines + Delta flying out of there. Sure, there's access to a lounge there via PP and the DL SkyClub, but they could make something really special if they wanted. Unless it would be an issue that it would fill up too quickly b/c too many people going through?

I think "The Lounge" closed, so maybe there's even space there for a new lounge!