Do you guys know about DietPi? I use it on two Raspberry Pi, just installed it on a Wyse mini-PC and I think it's really great:
Truly Optimised
DietPi is an extremely lightweight Debian OS, highly optimised for minimal CPU and RAM resource usage, ensuring your SBC always runs at its maximum potential.
Simple interface
DietPi programs use lightweight Whiptail menus. Spend less time staring at the command line, more time enjoying your Pi.
DietPi-Software
Quickly and easily install popular software "ready to run" and optimised for your system. Only the software you need is installed.
DietPi-Config
Quickly and effortlessly customise your device's hardware and software settings for your needs, including network connection and localisation setup.
DietPi-Backup
Quickly and easily backup or restore your DietPi system.
Logging System Choices
You decide how much logging you need. Get a performance boost with DietPi-RAMlog, or, rsyslog and logrotate for log critical servers.
DietPi-Services Control
Control which installed software has higher or lower priority levels: nice, affinity, policy scheduler and more.
DietPi-Update System
DietPi automatically checks for updates and informs you when they are available. Update instantly, without having to write a new image.
DietPi-Automation
Allows you to completely automate a DietPi installation with no user input. Simply by configuring dietpi.txt before powering on.
Given pihole's recent record with updates, I'm not sure I want them firing automatically.
Whether you automate pihole upgrades is separate from whether you automate debian package updates. I recommend at least automatically installing security updates for the OS, unless you want to manually keep track and do this for all your devices.