This is a recurring suggestion on these forums, but until somebody steps up and starts doing it, this is not going to happen. So what are you going to do to make this happen? Ugh, okay that is manager speak
But us Linux nerds & geeks are happy with the way it operates, as the way it works now allows us full control of our computing. What you describe already exists, and is called OSX. I however do not what my computer to hide control from me, and I prefer to learn how it works and the terminology comes with the learning. So "dumbing down" Linux Mint won't get any votes from me
Both Ubuntu and Linux Mint have a standard edition, so all the choices you describe users need to make do not apply for the average user. The average user, if trying Linux Mint, should be downloading the standard edition (Linux Mint 11 GNOME). Once you are comfortable with that you can start exploring other options. But the average user won't be inclined to do so.
A slimmed down version might be a good idea, but I think this is where things like Android tablets step in, or Jolicloud and other such efforts to target average users.
Apple with their iCloud is doing what you describe about backup up files in the cloud, and sharing those files also across your Apple devices automatically. Ubuntu has Ubuntu One for this and most users are familiar with Dropbox I think (hope) which runs on most major desktop and mobile platforms including Linux. Those, and lots of other cloud backup solutions, integrate very well with Linux desktop. I'm not sure what to add to this. Only thing I can say against it, is that any of the "average users" I know that have tried or are using Linux make just as much as mess of their system as they were capable of doing in Windows. They can be perfectly organized in meatspace but make a right old mess of their files on their computer... There is no helping that with any application, except rigorously locking down what users can do as Apple is doing with their devices.