I think a world without diversity would be monotone. The creators of the Community eliminated color because the people would notice that the weather is different everyday and colors have a wide variety, not just black and white. If a person thought one color to him was a different color to another person, that would cause conflict, destroying the reason Sameness was created.
We can see this because there was an extensive argument about a dress appearing to be white and gold or blue and black.
Many studies show that the dress was actually blue and black. It was the amount of the light which hit the dress that caused the mind to perceive that the dress looked like it was white and gold. Even though the answer has been determined, people are still debating about it.
Our society would be similar to a world full of robots. There would be no emotion, feelings, or creativity in the world. The world would just come to Sameness, just like in the book, The Giver.
No one would be able to experiment with anything. No one would have any creative freedom. That would lead to no new creations in life.
Everyone would be assigned a job to do for the rest of his life. No one would be able to explore what his real passion is. He would just be stuck with what someone thinks he is good at instead of what he liked. Someone would not be able to pursue what that person likes to do.
If we all wore the same clothes that we were assigned to and had the exact same type of house as everyone else, people would not feel unique or special. You could not even decorate your house for special occasions such as Christmas and Halloween. Nobody could add anything to their assigned clothing such as earrings and necklaces. Some people express themselves through their clothing and what they wear. Taking away that privilege, they would not be able to express themselves through their clothing.
Taking away the peoples creativity, emotions, weather, and other things would overall be a bad idea. The lack of creativity would result in a small amount of new inventions for the world. With everyone wearing the same outfit, the amount of bullying would decrease. Overall, I would not take the creativity, emotions, etc. away just for wanting to achieve Sameness in the world.
That would be too much of a risk and a poor decision. If that happened, everyone would listen to the leader obediently like a dog, but that would not teach them what it is like in the real world. It would just be better for the Elders to keep the colors, weather, music, etc. in the Community.