I have always felt that the courts played too fast and arcade-like, so I spent a lot of time doing research and matching up court bounces from real videos of matches on YouTube. I have done all courts except for a couple. Here is what I have so far (for each respective court.ini in Pak01.Pak and in some cases Pak02.Pak):
Red Clay--Friction: 0.47, Elasticity: 0.88, SurfaceSpeed: -0.75
Synthetic/Rebound Ace--Friction: 0.48, Elasticity: 0.86, SurfaceSpeed: -0.25
Indoor Carpet--Friction: 0.50, Elasticity: 0.86, SurfaceSpeed: 0
Indoor Hard--Friction: 0.49, Elasticity: 0.87, SurfaceSpeed: 0
Blue-Green Cement--Friction: 0.48, Elasticity: 0.89, SurfaceSpeed -0.25
Newline Synthetic--Friction: 0.47, Elasticity: 0.86, SurfaceSpeed: -0.40
Green Clay--Friction: 0.47, Elasticity: 0.87, SurfaceSpeed: -0.75
Haven't done grass or cement yet.
If people would try these out and let me know what you think, I would appreciate it. As I mentioned, I think the default parameters make the courts play way too fast, and I have been working on this for a long time to get it just right in my view.
Only do this for offline play against the CPU, and make sure to change back to the original values when you want to play online.