1 night layover in Paris

One idea we considered but did not choose was to stay somewhere like the Mont Royal in Chantilly and see the chateau and Senlis before heading to the airport. You are only 20-30 minutes from the airport. Maybe some other posters can speak as to whether these are worth doing since we went another direction.

Returning to Paris at what airport?

ORY is a much better option as it is closer to Paris with cheaper transportation options. From ORY, you could stay for the night, somewhere near St Michel or Luxembourg on the RER B line, (taxi fixed fare at 32€), be at a hotel in time to enjoy diner, then take the RER B to CDG the next morning.

If you arrive at CDG, it would be difficult to be back in Paris in time for diner, unless you could reserve somewhere 21h30 or later. Otherwise you could simply stay at an airport hotel.

I tried to fly into ORY but the flights didn't work out for us

Mont Royal looks great but says sold out

Stay somewhere close to the Seine as most attractions are close to the river. In the historic Marais neighborhood, the Hotel de la Bretonnerie is a classic French hotel with AC ( important to have AC this summer) and an elevator. They serve breakfast in their medieval basement. Around €200.

You’re between a rock and a hard place. For a 14:10 flight, giving yourself 4 hours to check in, 3 if in Business class, you have to leave Paris at 9:10 to be at the airport at 10:10. Is it worth the schleps, transportation cost to and from, and dinner after 9 pm?

My last flight I was in Business. I barely had time in the lounge when we had to hurry to the gate. For economy, people are reporting four hours.

I’d look for an airport hotel with some amenities ( pool at one of the Novotels for example) and relax.

There are a few other nice hotels in the area (e.g. Le Château De La Tour), so it may be worth checking what places would have availability.

I'd stay at an airport hotel easy access by train.