Though it was a coupe of years ago I was able to switch flights after checking in (was a regional guy with benefits). I recall I didn't have any checked bags but I think you'd be all right if you do. You can also try a ZED fare on Air France and the other US carriers (or Jumpseat) or just grab a train from Paris to numerous other airports Delta serves if the loads look better.
Last edited by FTFF; 12-21-2016 at 03:10 AM.
Reason: flow