pacom VS archtorify

There's a section on readme for how version locking means: https://github.com/kriansa/pacom#package-version-locking -- essentially, once you have approved a package to your local db, you can uninstall and reinstall it whenever you want and you won't be prompted to review it again (unless you want to update it or it's a VCS pkg). Then you can use that local db to distribute among other Arch instances you use, for instance.

tor is good and all but it's actually not as secure as it might seem, whoever controls the exit node controls the traffic, if you're using arch linux you can use something like this to make sure your session is secure

One alternative would be to install a regular linux distro that supports rpi and have all network settings go through the Tor network, e.g. Arch using Archtorify. But that means data is stored on the machine and you lose the whole live OS aspect that you get with Tails. One way round this is to have the OS saved on the SD Card and you can just unplug it when not in use, so it's always in your pocket. Not exactly a live distro but at least it's always in your possession. You could probably encrypt it, too.