I am not saying that's not a good idea, it's just a different scope. I am sure a RaspPI would make a great little console: but you have still to "target" the platform somehow, for example the kind of driver and such (gpu is mali, ardeno, tegra...? all drivers into a single arm live distro?)
PC desktop platform are, instead, made by design to be bundle with bunch of drivers. This make easier to build up a live distro just to run for a "itch" when you want to boot/reboot any "unknown" pc rig.