Do not forget about the certificate! Warning: The certificate used for encrypting the database encryption key has not been backed up. Imagine if you need to recover the backup and you can’t? You will get the dreaded thumbprint error.
Msg 33111, Level 16, State 3, Line 25 Cannot find server certificate with thumbprint ‘0x78FAB5A2A5D593FD3C4E163C90B745F70AB51233’. Msg 3013, Level 16, State 1, Line 25
RESTORE DATABASE is terminating abnormally.
So make sure you respect this certificate (and the key) and back it up and re-create them on the target server for a successful restore.
In SQL Server 2016 and 2017, there’s no reason not to encrypt backups; the marginal cost is practically nil even if you’re low enough on disk space that you need to do backup compression.