I would like to suggest that you develop a lesson for Ashokan Farewell by Jay Unger. I particularly like the arrangement that Sflier posted on your Student Review page. It doesn't appear to be a difficult piece and I like the mix of solo and accompaniment that is in Sflier's arrangement. I've checked arrangements on other websites and I like Sflier's the best.
If you know of a song that you think would make a good lesson, here is the place to bring it up. As of May, 2015 we have over 800 song lessons but are always on the lookout for more. Be sure to point out what about the song makes it a good candidate, unique or unusual, a particular part that interests you, or just that you think a bunch of members would enjoy it. An embedded video would be helpful as well.