Just put your system configuration in Ansible playbook. When your distro has new release, go through your changes and remove ones that are no longer relevant.
For home, I recommend a dotfiles repository with subdirectories for each tool, like bash, git, vim, etc. Use GNU stow to symlink the required files in place on each machine.
I have played 7D2D over the years, and can confirm the quality issues. I don't recommend this game. They could have made a masterpiece, but ultimately spent all time rewriting various systems in the game for no purpose.
But if you really have to back up the disk image, dd a copy of it, mount the copied image as loopback device, write the loopback filesystem full of /dev/zero, sync, delete the zero file(s), unmount, cp --sparse=always and store the result.
The reason for using the loopback image step is to prevent wearing out the SD card with writing the free space full of zeros every time you make a backup.
There may be an existing tool for this, but I don't remember it.
What are you running on, a dead badger?