My approach these days:

1. Hot live data on my laptop.

2. Archive dir on NAS.

It’s either 1 or 2, no overlap.

Then:

1. Backup whole laptop to USB bootable drive “when I fancy”.

2. Backup home dir to NAS using duplicacy. This is accessible via SFTP, so it works no matter where I am.

3. Backup the Archive dir of the NAS to cheap cloud storage.

Ideally I should add an external drive for the NAS to backup #3 locally, too.