I take daily btrfs snapshots, and use btrfs send/receive to sync them to an external drive. It’s really fast, even for huge files like virtual disks of VMs. It does require root, though.
I grew tired of filtering out cache files and such, and just backup everything, including the OS.
Just add a new adress book and choose “import an existing collection”. If you give it permissions, you can then select the Google account already on your device, and import it directly.