All of these places will make transport to the airport to be in the check out line 3 hours ahead difficult. Senlis which is closer is a better choice than any of these (all good towns but not at all convenient to the airport). I would only stay in Senlis if I also had a very good car service lined up ahead of time.
Why not day trip to these towns from Paris or even spend a night as a side trip from Paris and then spend that last night in Paris where it is so easy to get to the airport by cab or train. Paris is nearer to the airport from the perspective of convenience and actually getting there on time then any of these. And if you have a rental car, don't underestimate the hassles of getting the car turned in and a receipt showing no damage which you want before heading for your flight. It once took us 3 hours to get this documentation when we turned a car in at CDG that had been damaged when we took it. They wanted to confiscate our documentation without giving us a copy and thought they could wait us out because they assumed we had a plane to catch. We didn't. They finally got us the information in 3 hours. But a normal turn in with receipt of gas up and no damage is not like the US wher eit is 10 minutes -- speed and efficiency is not a French car rental thing.
You say you don't want an airport hotel but if I wanted to finish the trip in one of these towns then I would spend the day there and then drive to the airprt and turn in the car late in the evening after dinner in the town and spend the night at the airport where being in line at 9 am would be easy.
Trying to get to CDG from a small town the morning of the flight is not going to be a peaceful relaxed conclusion of your trip.
