Yellowstone & Black Hills

We'll be leaving labor day weekend for a three week trip from Utah via I-80 & 25 to the Black Hills, across central Wyoming to Yellowstone, then up to the Bitterroot valley in Western Montana for a little fishing, returning through Idaho to Salt Lake. I'd be interested in suggestions on what to see and even more important, what to pass on in Yellowstone and the Black Hills.

We have 4 nights planned at Rafter J Bar Rv park in the Black Hills. Obviously, Mt. Rushmore is on the agenda. What else should we see or avoid?

Then across Wyoming (a night in Riverton or Lander), through Grand Teton and the south entrance to Yellowstone. We have three nights at Fishing Bridge and then three nights at Madison campground. We understand that the latter is dry camping.

What to see in that time frame? Are the organized tours on the yellow buses worth the money? Anything to avoid? I saw the thread on Fishing Bridge. Anyone have experience at Madison?

We expect mid September to be nice in the Black Hills but cold in Yellowstone.

All advice will be gratefully received!