It seems like you're thinking of making members of a certain level moderators.

This could cause problems among members who have differing opinions about what is or isn't an appropriate post or comment.
Who's opinion overrides the others?

Maybe think about asking 3 or 4 members who spend a lot of time here, and have a high enough level, if they would like to be a moderator.

This would help decide the fate of questionable posts or comments by a few moderators discussing it via private messages rather than a large number members bickering about whether it should be allowed on the forum or not.

You could even make the moderators known to the rest of the forum by some identifying mark or color. They could officially warn offenders via PM's. Possibly give them the power to remove consistent rule breakers.