I get the impression that this park is busier than it used to be. It's ringed by suburbs (though it's big enough that you don't see/hear them from the trail), and while it wasn't crowded, there were a fair few joggers/trail runners.
Started hiking around 8am, which meant that we had shade for most of the trip; by early afternoon, though, I think most of the shade would be gone, and the trail would be pretty exposed.
We went as far as the Zizelmann House on the Joe Johnston trail, which meant that we saw the dino tracks and this really cool spot that was dripping with Spanish moss.
The tracks were okay--one site was covered in water, but in the other two we could see 3 theropad prints quite clearly and a thing that could be a sauropod track. They're roped off for preservation, which is fair enough, but it's nothing like as cool or as numerous as the tracks at Dinosaur Valley, or the Hill Country Heritage site, or the tracks in the San Gabriel river by Leander.