If that is really something to worry about you can just copy stuff off and drop the copy off at a relatives house. These days you can get 1-2TB 2.5" drives for cheap. Off site storage has become reasonably convenient even if you are moving physical objects around.
A) Cloud backup solutions already abstract away replicating multiple copies for redundancy.
Unless Google/Dropbox/Amazon/Microsoft go out of business, you are not likely to lose data from your backup via act of god (aka data center fire)
B) The simple interface of web solutions is still ultimately that if you want redundancy, just pick 2 (or 3) different providers. Myself - I use Google Drive for backup of my most core files, and Backblaze for the whole shabang.
