Just got back from a weekend at Kerrville-Schreiner and I must say that things have not changed much since the previous posters comments...
We had reserved a spot on the 'Riverside' of the park since we had planned on doing a bit of fishing and since it was close to the playground but when we got there and saw the water-only tent spots we quickly asked to look at the 'Hillside' campgrounds instead. The sites on the 'Riverside' were small, close together, and barely had any shade at all. They afforded very little privacy at all (in fact to be honest, none!). The only benefit we could see was that it was just a short stroll to a nice fishing dock/area that actually did have shade.
Oh and there were nearby bathrooms/showers (that were unfortunately closed for remodeling).
The 'Hillside' was MUCH better. We stayed in spot #57 which had plenty of shade and kept us well seperated from our neighbors. Short walk to clean restrooms/showers and water. Our site had a picnic table and a firering with grill. The only iffy thing about this site was that it appears to possibly have some run-off when it rains (evidence in the dirt since we just had rain the couple days before).
The park seemed pretty quiet, there were probably about 10 of the campsites around us occupied. Everyone was very friendly and quite a few families were around. My 6 year old daughter was thrilled when we went down to the fishing pier for the second time of the day and there was another family down there fishing as well. The kids had fun catching perch, crappie, and a little sunfish. (As a side note the father had caught a 3.5 lb bass the evening before, with a plastic frog, so there are bigger fish to be caught out there.)
The hiking trails are also nicely maintained. We picked up 2 or 3 pieces of trash on our little hike but that was about all we saw. Some of the trails had more shade than others but for the most part it was a nice walk with some minor changes in evelation. And with being so close to the road you don't really have to worry about getting lost.
Over-all while this is a small park and we weren't thrilled with being so far from the river it was worth it for a weekend trip, we would probably visit again.
Sorry for being so verbose but I hope that this review helps...
thanks!