That looks useful. Does it delete itself and the extra repo configuration after setup? If not, while convenient I'm not convinced the increased attack surface is worth it.
I must say it's silly we can't be trusted with a simple way to drop in a shell script on the SD card that runs at boot as root in rasbian.
I don't even understand the idea that it could be bad for newbies to maybe mess up. The whole point of the RPi was to give students a small, cheap, easy to repair computer with low-level features to learn with.
https://github.com/RPi-Distro/pi-gen/pull/207
The minor downside is that you have to build the image yourself, but fortunately that is a single command once docked is installed.