Development of any project benefits from the creation of requirements for its success. In the case of delaying humanity's extinction for as long as possible (similar to the fictional effort featured in the Simulated News blog), such requirements could feature aspects of a simulated alternative future that meet that criteria based on my research.
The following diagram shows two possible ways of categorizing such requirements, presented as a planning exercise for their development. In one way (1), the "global variables" in the simulation are explicitly listed, with their end states to be identified. The second way (2) is to specify basic characteristics for any and all applicable variables.
In the traditional top-down approach to defining projects in industry (such as software development), a simple statement or set of statements would be the basis for requirements that support them, with progressively more detail that ultimately and unambiguously defines the end-product.
For example, one such statement might be: "Humanity shall survive as long as possible without loss of population and with the maximum sustainable life expectancy and quality of life. " Note that this is also a value statement, prioritizing longevity and population above all else, a choice not everyone might agree with.