There are basically 2 extreme models... absolute freedom or the total control by some instance. In my opinion the first way can work but doesnt have to. The second just cannot.
At least in my definition of a "working" system.
Even if it where possible for anybody or a piece of software to manage all of our concerns, which is like you wrote, pretty impossible. We still would have the problem of electing the "best world leader" or wrinting down rules to every aspect of our life. Just like we tried :)
In order for total control to work, one would need every possible information about everything everytime... Like seen in some scifi movies.
I would not like to live in such a world... do you?