Tom - I can see why the PT-19 was so popular - it actually had flying tendencies(!) and was pretty docile, compared to planes like the Fokker Triplane which seemed like barely controllable flying bricks. Of course, they were eye-candy for kids, who wouldn't want one of those when they were 7-8 years old.
H5606 - I changed the pushrod placement tonight after you brought attention to your situation.
Once moved, I seemed to get a lot of throw.
Here's a still shot of the linkage with the pushrod moved to the shorter hole (more throw). I think it shows the webbing you are talking about on the stabilator, used for adding rigidity.
Also, a link to a video of the stabilator once I moved to the shorter hole in the control horn, tonight. A video is worth a million words.
Even used slo mo! (trying out a borrowed gopro for slo mo). Video
.