I'm suggesting not even installing other Desktop enviroments (although that sounds like a very good feature of Ubuntu, I'm afraid I haven't had the pleasure), just choosing what you want, this will avoid cluttering your hard drive with enviroments you don't use.
You probably feel that way simply because KDE is the default enviroment of Pardus lol

I agree wholeheartedly, KDE can be absolutely <awful>, its the only reason I stuck with Ubuntu for so long, Gnome has a cleaner crisper interface. But I feel that on Pardus, KDe is a model of stabilitily and customizability.