Spend some time at Fishing Bridge and West Yellowstone. When we were there in 1015, we only stayed at Fishing Bridge, but the travel time to various parts of the park can be long and involve traffic as well as bison slow downs. If doing it again, I would book 3 nights at Fishing Bridge and then 2 o r three nights at West Yellowstone......or longer at both if you have the time.
And, the Grand Tetons are magnificent. We also stayed at Coulter Bay. Make sure you take the tram to the top of the mountain at Jackson Hole. We found the Tetons to be much more relaxing than Yellowstone. And, if you can, move right on up to Glacier NP as it is also amazing. We only got as far east as Logan Pass, but what an experience.
Have a great time!