[themodelplumber]

sudo rsync -vax --delete --ignore-errors --xattrs --acls / /media/destination/partition/

This is run periodically via your favorite method. You can then boot off the backup destination drive later if needed (GRUB picks it up when plugged in). This seems to work fine for me.

BTW generally "broke everything" ought to be listed out, clarified, etc. so you can understand or document your system better. The notes you keep about it can help future upgrades complete with fewer issues.