Whilst I fully accept that Hard Drives do indeed fail, and me being an old 'belt and braces' codger I have a drive offsite too BUT I feel that the chances of your cloud AND your HDD going belly up at the same time pretty slim. Shirley as soon as one went up the pictures then immediate steps...
I'm a bit old school, have a 4Tb Network Drive with all my photos, music and videos on. Can access anywhere using relevant app (WD My Cloud in this instance) but backed up on a 4Tb Hard Drive.
Simples.