I have a lot of respect for lean programs. I've been building my own hand-coded assembly kernel for the last few years as I have a fascination with lean, mean programming. However, KDE does offer a lot of very useful functionality that is an honest time-saver. I'm an akonadi+nepomuk convert. I also love KIO and Kate.
IMHO, if I was going for lean, I wouldn't be using a GUI anyway. Definitely not for Linux sysadmin tasks!