If we will have free will and be sinless in Heaven at the same time, then why did God not create a world with sinless free creatures to begin with?

This question is scoped to those who believe that: - We have [libertarian free wills](https://en.wikipedia.org/wiki/Libertarianism_(metaphysics)) - We will retain our free will in Heaven - We will be sinless in Heaven **Question**: If Heaven demonstrates that it is possible to live in a world where (1) there is no sin and (2) everyone has free will, then why did God not create a world like that to begin with? The Garden of Eden was a place where Adam & Eve had free will but could sin (in fact, they did), whereas Heaven (after Jesus' second coming) will be a place where everyone will have free will and yet will never sin. Is there a fundamental difference between the nature or the setting of Adam & Eve and the nature or the setting of the saints in Heaven? If so, why?