How about a series featuring real-life material (anime, manga, news articles, songs etc.) to decipher for ourselves with a solution from the teacher team attached? For instance, I really loved the "Japanese with Poster Phrases" series. It's such a shame it wasn't continued.
I think this would really match the idea of a FUN and educational format to learn Japanese. I for my part, learned English mainly through media (movies and books). I would love to do so with Japanese, too. But alas my skills are too poor to get going with the interesting stuff. I tried translating some song lyrics once but that was quite frustrating because after looking up every 2nd word in a dictionary I wasn't even sure if I got the right grasp of the grammatical structure which had been used (as there is no such thing as a 'solution') or whether I just wrote a completely new song...
The main issue with the more famous media is probably the copyright but there is probably still some less known material out there which could be used, isn't there?
Keep up the good work,