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Windows deformation when you drag them around gives an interesting visual feedback. It's also a good visual representation for Maximize/Minimize. I personally don't have it when a Window opens, though, and I believe that this is default (I don't remember changing it).
That said, if you don't like it, just turn it off. It's as simply as unchecking a single checkbox.
As for the Window Switcher, Windows are only partially covered when you have *lots* of them open...however, you can change the shape of the ellipse in order to minimize this, if you want.
I do agree with you for the default screen configuration...however, there are issues with the number of desktops with KDE, this might be why the default is the (safe) 1x4 configuration.