I think a 15 post daily commitment is a good start to anyone applying, seeing as the daily requirement posting average is 15 post per day.

Myself and Dave just post a lot because we keep replying to each other's post and we are online at the same time a lot of the time.

So just telling everyone else that, who wants to apply. You don't need to make 100 - 300 post per day. I think just showing up with at LEAST 15 post per day is solid. I've seen some mods who doesn't even do that.... so it's just about keeping the board active, not letting it go 48 hours without a reply and things like that.

Being a mod isn't that difficult, especially if you don't have 4 or 5 boards.
Kate, I understand your situation because I remember the time where I just didn't want to mod, and just post for the enjoyment. It's good not to have any commitments or anything.