No question in my mind Grand Teton is much more spectacular than YNP. Since you have a genny & apparently are happy to use it the dry camping Gros Ventre is the place to stay. There are a few electric sites too. Sites are separated much more than Colter Bay & it is very close to the Mormon Barn. Reservations are only necessary over the July 4th holiday period. We were there one July 4th weekend & it was only full one night.
If you like hiking & biking you could do four days easy just in Teton.
No matter where you go, two weeks is one ambitious trip from Indiana.
