The SystemD KCM is a little hard to find when sys-settings is opened. Given it central nature it should be somewhere in the upper part of the window in ICON mode and not stashed away at the very bottom in "sidebar view mode". At the bottom please put the less important stuff such as Konqueror agent-string settings, cookies and other less relevant stuff.
I don't see how it's hard to find at all. It has a top-level placement in the hierarchy and is therefore easier to find than most things! It even gets its own category all to itself.