We stayed at walk-in campsite W1 and it was amazing! The campsite was very secluded from the campground, we never heard a single screaming child or barking dog. If you are parking in the main campground area the walk-in campsites are at the top of a substantial hill which is good because it acts as a deterrent for most people and makes the site feel even more private.
We camped there on a Thursday night/Friday morning we saw very few people on the trails, in the campground, and the entire park in general.
There are several extensive prairie restorations, wooded floodplain areas, and beautiful overlooks. Plenty of interesting botany and birding to be had here.