Let's explain the situations that you might need to consider when working out how to protect your data. In this circumstance "protect" doesn't mean preventing unauthorised access, but acting to ensure that some sort of technical or other catastrophe - e.g. physical disc failure, fire, flood, theft etc.
I have a 4 bay NAS at home. My home PC saves its data to this NAS. The 4 discs in this device can survive a single disc failure, and I can "hot swap" the failed disc if one should fail, and the unit will rebuild the data across the 4 discs. This data is then backed up (2200 at night) through a service in the cloud from the manufacturer, and gives me individual daily points of time that I can restore to - from one file to the whole shooting match.
In addition, (being an Office 365 user with 1TB storage on MS OneDrive cloud) files that I want to access from anywhere are synchronised with that service.
The security that this gives me varies from being able to replace my main PC without loads of data transfer (I just connect the new PC to the folders on the NAS - 5 minute job) through when I make changes to a document and screw it up beyond all recognition I can revert to a previous version through the backup service to being able to recover the whole lot if the house goes up in smoke...
Overkill? Possibly, but my whole IT life is much easier to manage...