DH and I have two favorites that we like to visit and revisit - Baker's Hole FS CG, 2 miles north of West Yellowstone. Most sites have electricity, big rig easy in and out and great views all around. Next would be Falls off the Togwotee Pass between The Grand Tetons and Dubois, Wyoming. One loop as electricity with pull throughs for big rigs. I too like Colter Bay, the RV sites, because it's beautiful for an RV park and amenities are great. I love walking over to the gift shop and convenience store. There's a museum there and two cafe's, as well as easy distance to the lake and great walking trails. DH does doesn't like Colter Bay though because the sites are too close together.