Approval voting guarantees the election of greatest possible consensus winners, when it ask voters "which alternatives do you consent to?"
Approval would vastly improve things, but has some drawbacks. Score is like Approval, but a bit more so, and then STAR takes Score and adds to it again to be an even better system.
The systems above all break two party dominance, or rather they make it impossible to enforce two party dominance. Ordinal systems on the other hand, all fall victim to Arrow's theorem, and thus reinforce two-party dominance.
So unanimous consensus? As in, something akin to expecting the tooth fairy to come wipe for you? There's no such system.
The closest thing is called Approval, and even with that system, there will be people who go away unhappy. Just far fewer of them than under any other voting system,
Perfect consensus only happen if there are dozens or even hundreds of people running for office, and only then if the voters have perfect knowledge of every candidate.
That's the key difference. A tiny group of people can reach consensus, a large group literally cannot. Not when electing a representative, or even setting policy through direct voting.
The origins of the word libertarian were actually closest to being anarchist. But that shit doesn't work.
The whole, no government just neighbors who talk to each other sounds great on paper, but fails the second the community has more than about 150 people.
There's a reason why Amish and Mennonite communities formally split at 150 people. Because our brains cannot handle it.
>The origins of the word libertarian were actually closest to being anarchist.
"libertarian socialists", yea. it's great that you mentioned the amish but you didn't finish explaining why they are relevant: anabaptists are the majority of christian anarchists.