We stayed at Fishing bridge many years ago.
The sights are tight no question.
No camp fires as I recall but we didn't care!!
IF you have never been to Yellowstone you need to consider location....
Yellowstone is a very big park!! It can take a couple hours to get from
where you are staying to where you want to be in the park.
That's 2 hours each way! That's a lot of your day.
If there are buffalo near a main road it quickly becomes a parking lot!
If you are heading to a far off corner of the park and the cars in
front of you want pictures of big animals you are stuck!
Fishing bridge is more or less central and as others have mentioned
it has a lot going on around it.
We divided the park into 4 "corners" and went in a different direction
every day. We're hikers and our kids are grown so we didn't have them
to contend with. If you've got kids that may change how you operate
in the park.
Fishing bridge will work! It's not gonna be the best RV campground you
ever saw but it could very well be in the middle of the best National Park
you ever visited!
Enjoy your trip!!