Idle thought: would it be better to instead extend the EWR AirTrain to Newark Penn when it's replaced? It's about 2.5 miles further, which is not really all that far when you consider that the JFK AirTrain is about 2.5 miles from Jamaica to Federal Circle. I assume Amtrak and NJTransit would be all in favor since closing the EWR mainline station would simplify their operations.
Of course there are benefits to extending PATH (direct city access, possibility of infill stations), just wondering if this has been considered.
Welcome to New York Penn Station. You are in a maze of twisty little passages, all alike.