We have a Suggestions Forum for posting ideas about changes or additions to the site, may want to repost this there.
Though it sounds like a difficult idea, finding someone to commit to teaching it, and qualified. Also, with so many varying beliefs, it would cause problems as i see it. What if the preacher was baptist? Then the charismatics will complain. While people complain about denominations, they exist for a reason. And this site has many different denominations.