@doggywuv is on the right track. You wouldn’t want standardization of society or culture because that would make human society less fit and less able to survive the coming shocks. No one knows what those shocks will be, but we can be certain they will come, sooner or later. We need to have every type of human governance possible, in case one of them turns out to be better than all the others at adapting to the shock.
There is no “best.” It’s all about adaptation. We like to think that democracy with capitalism is more adaptable, but that may or may not be the case. There may be situations where a more cooperative society or a more dictatorial society will have a survival advantage. It is best, hard as it may be to believe, to have all kinds of human systems in action at any one time, including the lawlessness of the Congo and the harsh dictatorial nature of the North Korean regime.
Those are, of course, regimes that are several standard deviations from the norm, and those of us in the middle of the bell curve might find them heinous, but you never know. They might turn out to be what saves humanity, unlikely as that may seem.
In any case, if you ask what country has the best laws, you have to go much further than you have in establishing criteria by which to determine what the “best” is. Your “optimally beneficial” is so vague as to be meaningless. Presumably we already have the optimally beneficial mix of laws in the world. They are the result of all human history. And, as I say, no one knows what will happen in the future, so we can’t possibly know what the optimally beneficial laws are, especially since there is no one optimally beneficial system that can adapt the best to all possible circumstances.
I’m sure you meant well in asking this question. Maybe you were hoping for people to put up some candidates, and then have a debate over whether they are good candidates or not. However, I think that’s putting the cart before the horse. First you need criteria by which to judge legal systems. From your standard of “optimally beneficial,” it sounds like you are a utilitarianist. A follower of John Stuart Mill.
That’s all well and good, but how do you define “good?” Who gets to decide what is good? If it is every individual combining individual goods into some kind collective good soup, how would you measure such a thing? And at what moment would you measure it? What would you do about change—it happens every second. The greatest good now may not be the same as the greatest good now.
So I’m not at all sure what you’re trying to get at, or what you imagine might be possible to get at. I don’t know what kind of discussion you were hoping to stimulate—presumably not a meta-discussion. But, without generating the rules of a discussion first, you really can’t have a meaningful discussion. It’s just a mess, like humanity.