If you're looking just to tone things down, and not a perfect world, trust me, we're going in the right direction like everybody says...
Most people are willing to accept others, just that there are some that are more open and some that are less.
But what makes you think that sameness is a bad thing?
Human history travels in waves; times of peace, times of war, and times that history doesn't remember because nothing really happens LOL. Maybe we can learn something if we all become same for a while. The sameness can't last forever, and there will be quite a bit of chaos, but it might be a valuable lesson. Not saying it will, since probably a whole lot of humanity and history will be lost, just saying it might.
And I love the Giver! :D Never read Brave New World, my teacher recommended it to me though since I told her I liked 1948 and Animal Farm.