Church is Youth Group grown up. We like to have our cliques, we like to have our entertainment, and we like to have our illusion of surprise.
How would the youth feel about having John the Baptizer as their youth leader in all his wilderness intensity, his weird smell, and dirty look, and honey in his beard? (And we recoil: How could this man possibly teach rowdy teenagers?)
We like to have the right amount of humour, the right inflection, the hand gestures, the relevant, the casual and the cool, reflected in any preacher. We actually feel entitled to this or they are not worth our time. Give someone two minutes and if they fail our first impression our brains automatically check out for the rest of it. If we can't opt for Jesus or John leading our youth groups, I think that says more about ourselves and our church than about our youth groups.
Perhaps, people would be more surprised listening to someone who doesn't look like themselves and sound like themselves and actually hear what they have to say. What if they had a super strong personality, or what if it was weak? What would it matter? I sometimes wonder that if people actually took the time to hear someone out without all the trappings of power point and pzazz, could they still decipher the word of God, and would they be able to recognize it even if it bit them in the ass?