I'm still contemplating JFK. Flight arrives at 9:30pm and can check-in for my next one around 5am or so and then hit a lounge.
Have a HIX booked for $186 / £115 but doesn't seem overly worth it for a little over 5 hours after travelling back and forth, waiting for any checked baggage etc.
Secondary option was to head into Queens and stay at a hostel for the time but that would take a good couple of hours on the AirTrain and subway (would waste some time for $11 or so each way I suppose)
May see if I can check my bag on the flight into JFK through to my destination the following day as this would save my dragging it around.