@
marconique - notwithstanding what other responders have posted, here's something you should perhaps consider.
Would you regard the 'personal' folder structure you have in the cloud as the backup source for your calibre library
If so, have you
- devised a process for using it as a recovery source should your calibre library become unusable (eg device fail),
- have you documented the process,
- have you tested the process.
The only reason one does backups is to enable one do to a restore. At the time of wanting to do a restore one is almost invariably stressed, and it's hopefully not something one needs to do often, so doing a restore should be as simple as possible to execute.
BR