This is not the answer you were looking for, but a GREAT editor is a really good investment.
A great editor would know what types of articles would be popular, who would be able to handle the topic best (i.e., who would have a certain level of expertise in the area), and how to provide constructive criticism to the writers.
and the better the writers you have, the better the editor you need. Great writers need great editors.
I hope this helps.
(Experience: Four years as a journalist writing for print newspapers and business magazines.)