Well someone has already done it for themselves.
Ubuntu All-In-One
Never disagreed with the idea just the part of asking Canonical to do it.Plan is to bring Ubuntu and some of the official derivatives (Kubuntu, Ubuntu Gnome, Xubuntu and Lubuntu) on one iso file that can be burnt on one DVD or USB flash drive. Every one of them can be used as Live system, with no need of installation on hard drive, or can be eventually installed on computer for full Ubuntu or any other system experience.
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