If you run into a UID-problem grsync can be a useful tool, as you can choose to "switch-off" preserving permissions.
Deja-dup, the backup software included in Ubuntu-Mate make "compressed", "incremental" backups - you need a copy of deja-dup to access the backup again. With grsync you can make an uncompressed backup that you can access from any attached Linux computer. My personal backup strategy uses both.
