Here is what I did: After downloading the 10_CoreCDX.iso I browsed through the package list of my Gentoo installation and used that as a basis for a clean, small KDE installation with equo.
Am I correct that there are no sets for this? Why? It would be a beautiful way to provide the not-so-experienced-users with robust preselections like "kde-minimal" and so on...
Besides that, I love it. I love how my experience with Gentoo helps me with Sabayon and that the config files are actually where I expect them

It seems that my search for a reliable, easy-to-maintain binary distro has come to an end.