The One Above did not want His creation to be a sort of simple oneness, homogeneous and uniform, with no distinction between one creation and the next. On the contrary, He desired a multitude—a tremendous multitude, to the point that we exclaim, “How many are Your works, oh G‑d!”
And not in number alone. They are diverse, and their diversity has great meaning. Upon beholding any one of those creations we can exclaim, “How great are Your works, oh G‑d!” Because these differences are not insignificant, arbitrary differences. Rather, the uniqueness of each individual creation is a commentary all of its own on the greatness of its Creator.
So too, it is the differences among human beings, not their sameness, that makes them precious in their Creator’s eyes.
This notion ("why all the variety?") still puzzles me.
I had a dream where I was seated across from an elderly jew (greying red hair, thick long peyot).
I asked this question -- why not keep things simple? and got an answer: "Because then there would be no connection!" which didn't resolve it for me. But then we were quiet together for a few seconds, and I felt a warm presence over us both...apparently the moment of silence gave me the answer I needed more than the words.