Not the parent, but if you're ever looking for features to implement:

I've been thinking about this for quite a while, and one reason I've been unhappy with any sort of cloud backup solution is that they're usually too slow for laptops, unless I leave them awake while I'm sleeping.

An ideal backup solution for me would be laptop > NAS (or desktop) > cloud. A backup over the local network should be magnitudes faster, and the always-on NAS can handle a slower, versioned backup to cloud storage.