Systems similar to this have been proposed in the past -- probably repeatedly. For example, although you probably wouldn't want such a system to be purely karma-based, you could still implement it by selecting a handful of the users that you thought represented the kind of community you wanted.

You could establish influence as a factor of a user's "distance" from the community's founders: you'd have the founders, the founders' friends, the founders' friends' friends, and so on, each with diminishing influence in community moderation.

However, this and other suggestions are not new, and pg doesn't tend to comment on them.

So in the end it's all a waste of effort.