Not a bad idea, I'll grant you that. I don't think the examples of trolls or pirates changes the discussion. If you use an alternate, you have to split your stake to do it, which in that case there's not much of a difference in treating this as two independent entities.
For now, it's what we have. Keep in mind that the community can and should counter the flag effects of a misbehaving flagger. But if there can be change to make this consensus better, I'm game. Same applies to upvotes in my opinion.