The current achievement system wouldn't track "first" category nor would it compare article names to those on a list.
What I'm hoping to accomplish is more focused and in that way theoretically have higher quality.
The key is drawing contributors attention to a list. It would give visitors some better direction for how they can contribute in case they don't have that idea or are looking for something specific.
The other piece is recognition. many people like getting recognized for their efforts. when they think they'll get recognition, they may be inclined to put in a little more effort which in principle helps quality and discourages vandalism.
alternative to a points system would be a voting system but that requires both a larger pool of contributors to begin with and more effort to maintain.
Do you have other suggestions on attracting and retaining good contributors?
sounds to me like a campaign to identify wikis that share some significant characteristics in common with The Expanse is in order. followed by a little lurking. finally a round of friendly direct messaging