Setup wise: I've let it choose what to backup itself.
you do need to confirm what it is backing up, that any folders you might have at root level (i keep media files there), and the likes of appdata folders (containing email folders), plus other obscure locations, are included.
Also perform some restores of data (dry-runs) to make sure it will work if armagedon arrives.
...with the discussion on delayed activation viruses - has any ransomware been delivered yet, in this way ?
simultaneously encrypting data on multiple servers & private machines at a pre-scheduled time, would probably do the most damage and give least possible time for an A/V response.
stuxnet was probably delayed activation but was not a ransomware (just destruction)
Although the data, rather than the hardware, probably has the most value, could you deliver a ransomware to private machines (A la stuxnet) that would render the hardware unusuable if ransom not payed.