One major hazard is consumer-grade Internet service that has onerous terms that prohibit running servers from a home connection, for any number of reasons. (Some would see this as cultural complicitness with “client/server as technosocial class division”, but the effect is similar regardless of how it's spun.) A related technical problem is the use of carrier NAT, which gets very tricky to traverse.

So actually getting devices to call home to the “personal cloud” seems like it would be harder to make happen, and more importantly, harder to make reliable, because you can't use economic power to force at least one side to act in a convenient manner. This would drain the life out of any attempt at “you don't have to think about it very much”.