b) Disk cloning/image type backup regimes.... (you're wasting a lot of time and space backing up Operating System and Software, both of which you can and should reinstall from scratch.... focus your efforts on backing up files which you can't restore by other means). Plus you won't really get a true clone/image of your disk unless you unmount it, boot of something else and clone it.
It is backing up the operating system and software which I would regard as the problem, particularly where re-installation may well not be possible simply because the software is no longer available.