My gut tells me that cloud-based OSes have too much of a user-server lag? I could be wrong. I don't claim to have all the answers for this worked out, TBH - otherwise I'd be starting a company that's working on this problem. I do think it's an avenue to be explored, though.

But as far as document storage, Maybe the dock acts as a home server? Either way, it seems like off-device document storage is a problem that's been solved multiple ways already?