So much to say here. I think this is an important issue. Being kid-like is central to being creative. But at the same time, being adult-like is central to being productive. The key isn't to become a creative kid who does nothing productive any more than it is to become an adult who does a lot but accomplishes nothing[1].
A few other thoughts on this subject:
I don't think that being child-like necessarily means one should think less. You just have to think differently. We adults have lots of experience that makes us think a certain way. Part of going back to being a kid is in learning to think in ways that bypasses that experience. For example, experience has taught me that Java is the best language to use for a team of 100 programmers. But I'm going to use Python for reasons x, y, and z.
Nor do I think it's a compliment to be called overly kid-like. Bear something else in mind: kids are fairly self-centered. They're at the stage in life where everything is about them. Everybody drops what they're doing to take care of them. Narcissists are people who are essentially frozen at this stage in time. This is why some people have noticed that there's a correlation between narcissism and creativity[2].
All the above noted, I do think that we as adults need to remind ourselves that we can't be adults all the time. It's just a question of when the time is appropriate, which can be very difficult to determine.
Did you know that we invented children? Children don’t exist.
I realize the irony in my thinking to refute a statement that's intended to point out why you shouldn't think. But this is a non-sequitur. We invented laptops, and there's a laptop right in front of me to prove that it exists. Race and gender are invented concepts as well, and they have a very real impact on our day-to-day lives.
[1] Shameless plug, I've already written on this subject: http://jasonmbaker.com/how-to-be-creative
[2] http://www.fastcompany.com/1701676/narcissism-and-creativity...