Hi,
RE:
> Removing packages in post can break including the livecd-desktop ks in
> other ks (which is a recommend practice) if the other ks needs any of
> the removed packages.
> The yum remove in post should be removed.
I am not sure what exactly 'removing packages in post can break' should mean, but removing 'remove' in YUM is not an idea of first brilliance.
At the beginning when I started using Fedora I really had some problems when removing packages but there is no problem when one installs 'orthogonal' packages (not sharing libraries, dictionaries, inference engines, imported objects, etc.).
Thus for example you can install and uninstall Adobe Reader as much as you like and nothing will happen to the OS.
Regards