Okay, I reread your post, and let me give you a more complete answer...
We paid $99pp/each way, plus taxes & fees for our May trip out of SWF.
We are waiting to book our fall trip, as our return in November is not published yet. I did see the same rate out of HPN. EWR is too far for us.
I actually work out of the HPN airport, so I just leave my car at work for free. 
MG
I had been checking for our Sept/Oct trip, too. I was so used to seeing "Sept 4" that I was surprised to see prices pop up, and even more surprised when I saw the prices. I thought we lucked out when we paid $69 ea way for our May trip (SWF-MCO - we were going to be on the same date schedule as you, but had to change our departure date to the 14th once we decided to bring along another DGS). However, timing was good again. This time, the price for Sept/Oct is $99 ea way from SWF, but EWR is only $59. Multiply x4, and it makes a measurable $$ difference for us. We're closer to EWR, but SWF is not too bad a ride, plus pkg is 1/2 the price.
The other problem with SWF in Sept/Oct is the flight times. In May our outbound flight is 8:00 AM from SWF, but that flight doesn't exist or isn't avail in Sept., nor are the later return flights from MCO, but I'm not sure why. We like to fly to WDW early and return on the mid-afternoon or evening flights.
Free parking is nice

, but is the parking truly "very limited" at HPN for most travelers? Once I read that on the airport site I stopped pricing flights from there, as it is too far for us to use a car service there and back. Now that I know you work out of there, maybe you could share some info on the accuracy of this?

HPN is about the same distance as SWF for us, so it would put it back in to play if we could park there or even at a nearby off site parking facility if one exists.
Well, maybe we'll be on the same flight on the 25th - we'll be the exhausted elders being dragged along by two rambunctious four year olds, so I'm asking for your forgiveness in advance, just in case
