I still can't find a way of changing the default white color of applications window backgrounds. It does hurt my eyes and I used to adjust it so easily up to 10.04.
There was this post: How to change the background colour of a window?, explaining how to tweak some things, but they don't affect the white background.
Also another sufferer tried to ask the question How to change the window color (default: white)? but it was closed! Please help.