PS: This is actually something where a simple user can contribute. There was a mailing list discussion about that where somebody even offered help, but nothing came out of it so far: http://lists.opensuse.org/opensuse-kde/2016-06/msg00040.html If you do want to work on that, see here for some pointers: https://bugzilla.opensuse.org/show_bug.cgi?id=985937#c2 The theme icons are just SVG files which you can edit with inkscape e.g. The network icons are in /usr/share/plasma/desktoptheme/XXXXX/icons/network.svgz. Have a look at the ones from the "default" theme to see what is missing.