Crisco makes chewier cookies that hold their shape more; butter ones tend to flatten, which helps with the crispiness.

I've found that letting the flavors blend for a day does help the final product.

Also, I subscribe to the NYT online, if you want me to look up a recipe. (I didn't find anything about the world's best CC cookies; they have an awful lot of CC cookie recipes though. And now I want cookies.)