Interesting. In my dealings with younger (and older) kids, thinking of them as little people seems to work well. Little, fully complete people, with many parts dramatically simpler (and more straightforward) than adults.
But then, I also think of adults as glorified chimps. Many parts are somewhat more complex -- though if you look closely enough, you'll see that much of the complexity is more of a veneer than anything deep.
Basic human nature shows through more with kids. Much of human nature is animal nature. Growing up seems to be mostly about setting those impulses against each other and delaying, suppressing, and avoiding the manifestations. In the process, we convince ourselves that we've had earth-shaking fundamental realizations about Truth and Beauty and Morality that lesser beings like children could never comprehend, as we go about our day with a sippy cup of caffeine in one hand, capturing the value that others have created as we lie and deceive to advance our supposedly noble goals, shoulder to shoulder with the rest of the herd.