Looking at the final diagram in the article, though you've achieved your aim of redundant backup, it certainly ISN'T any simpler. If anything, it's a LOT more complex than simply buying dropbox storage and dumping everything there.
true -- it's more complicated. However I wanted encrypted at rest documents (and that's hard with Dropbox), and I need backup - not just sync, so Dropbox can only provide half the solution.
This isn’t high art, but perhaps it will be useful to others. Getting my family data reasonably well backed up and synchronized between our many devices was a harder problem that I expected it to be.