I've been working on some non-pae installation/conversion options for 12.04 and wanted to give you a heads up in case you hadn't already considered the implications for the DE conversion part of your great tutorials.
You probably know that Ubuntu, Kubuntu, and probably Edubuntu will ship with the PAE kernel in 12.04, but both Lubuntu and Xubuntu will ship with non-pae.
As I've tried to parse the conversion from a non-pae Lubuntu install to Ubuntu it's important to note that one must be sure to watch what's going on with the packages "linux-headers-<version-number>-generic-pae" and "linux-headers-generic-pae", or most importantly the removal of the non-pae versions if converting Lubuntu or Xubuntu to one of the other DE's on a machine that lacks PAE kernel support.
On a side note, probably something you've already considered, I find it's best to never remove any plymouth theme or lightdm greeter packages.
If you wish you can read more here:
Hope I'm not just being a pain in your neck