I'm a fan of a couple of south central state parks. Fowlers Hollow SP and Colonel Denning SP. Fowlers Hollow is primitive, but in a very nice valley surrounded by a couple of mountains, and Colonel Denning is just very nicely kept up.
I never camped at Ole Bull becasue our camp is right up the hill from there, but we have fished, swam and pcinicked there with the kids ...I gotta agree, it is in a great spot and nice set-up for family cmaping and great HQ area for touring.
The only down side with Ole Bull SP is the camping area does not have alot of privacy between camper sites, be nice if they left a little green space between the spots but being under all those tall pines likely would not let much grow anyway. To me it seems to defeat the purpose of going all the way to Potter with camper in tow to set it there 15' from the other guy. But that is true in just about any campsite. Just seems amplified up there since you are surrounded by a million miles of woods with spots no human likely sees all year long.