Greek Natural Method - audio recordings may be useful in the early stages of language learning to get the sounds of the words in reconstructed koine rather than Erasmian pronunciation. What I've found with some of the recordings that are available is that they are of insufficient quality -- it's difficult to hear the right sound construction. In your video of the classroom presentation, I never did get the pronunciation of "cup" or "mug" especially once the class started repeating.
sm: Yes, I would agree across the board here. Listening to audio that accompanies text can really give one a feel for the language. This is something I enjoyed with Lingua Latina, and I have enjoyed Buth's recordings as well. I have in mind to do some recordings of texts particularly to help promote reconstructed Koine readings.
The video I put up was not meant as a teaching aid as much as a demonstration. It will probably be another two months before I start trying to record some teaching videos, and they will just feature me in a fairly empty set, with hopefully few audio distractions.
A neo-koine lexicon - this would be quite useful for constructing dialog in one's head ("I am starting my car
sm: Yes, if one wants to discuss contemporary things it is essential to have words for them. While talking in Koine has some more challenges in terms of vocabulary than, say, neo-Latin, they are only challenges of vocabulary.
There are already so many Lexica available I'm not sure that including non-contemporary things would be necessary (although being able to look up both contemporary and non-contemporary things in one place would be easier).
sm: I think part of the challenge is knowing what to include and what to exclude; the way I am proceeding at present, it may be possible to create both: one a word list with all sorts of terms to help composition, and a narrower list that singles out specifically neologisms.
Video resources - using pictures to link word sounds to images is beneficial. However, as mentioned previously, and especially in video where compression rates are very high, the audio needs to be clear. I've seen so many Greek videos where the audio is barely understandable either because of poor audio recording or compression artifacts.
sm: Certainly agreed, clear audio is critical.
I think Randall Buth's method of using simple drawings with clear audio is the best solution.
sm: I quite like Buth's work, as I have always said. However the main barrier for me to having simple drawings is that neither can I draw, nor do I have a close acquaintance who can. If someone out there wants to volunteer, I could think more along including drawings in some works, especially the GNM.