Some of courts are very bright, looks ugly and ball is barely visible.
Here is short tutorial (thanks to Elias), how to copy and replace one court with another one. For example you can have Roland Garros court in Rome, Nice etc.
1) At first you need program to edit .pak files, like Qped
You can download it from here (works without installing)
https://rapidu.net/4920632580/QPed.rar
2)
quit from game first, if you have it opened
open program Qped and open file [GAME FOLDER]\Mods\ITST118\Data\pak03.pak
3) in catalog's tree - go to "data" and you have view of all courts in game, in every folder there is a file with court's name/city so you can recognize which court it is
4)
In Qped go to folder with court which you don't like and want to change, delete original "courttex.jpg" file (edit/delete).
5)
Pick one nice court and check what is its number in "data" folder. Now you have to extract file "courttex.jpg" from this folder somewhere on your disk (object/export to file).
6)
In Qped go back to folder where you deleted earlier "courttex.jpg", in windows explorer - drag extracted earlier file "courttex.jpg" (nice court) to folder in Qped.
7)
That's all. At end you have to save file pak03.pak and exit from program.
You can extract also all catalog "data" with all courts, if you want to browse it on disk (~200mb on disk).