I've been to this park a few times and really enjoy riding the 19-mile loop there. It's not "difficult" riding at all, has some great open spaces to gait or canter, and some areas that run alongside the water are quite pretty.
In wet weather, I think some of the areas have potential to get a little sloppy if they are used heavily. However, our horses were kicking up (a lot of) dust during our recent rides and it was great!
Trails are well-maintained and well-marked, it looks as though they have made recent improvements to some areas (gravel, drainage, etc) and with well-spaced rest areas to tie the horses when you need to take a break.
I have never camped there but I think they have just recently put in water lines and there is a nice little covered pavilion with picnic tables.
It's a shame that the state of Ohio acts as though it would rather not have horses or horse-campers in the parks at all, but the local OHC has done a fantastic job of making Caesar Creek an enjoyable place to ride!