I would expect a moderator on this site to be knowledgeable about running websites. A good answer history would demonstrate this. Certainly, some degree of expertise is needed to know when questions are off-topic and should be closed.
On the other hand, I would rather vote for a moderator that is patient, fair, and willing to help over a less helpful expert. I would like to see a candidate that has patrolled for spam and flagged posts, helped other users by commenting on posts, and shown that they can edit posts for spelling, grammar, and clarity.