>>1
From what I've seen, KDE apps don't have much in the way of default shortcut keys (a default installation of the Gwenview image viewer has only 33 keyboard shortcuts defined), but the ability for users to define their own shortcut keys is extensive.

Thanks to the way the underlying toolkit is designed, pretty much anything that has a menu entry or a toolbutton (and some that have neither, like Konqueror's Ctrl+E shortcut for stopping gif animations) can be assigned a shortcut.