I think your model is pretty decent. But the recent crash down to 4,000 came, likely, as a result of the binance FUD that was circulating around today about a hack. Further, we are in completely new territory when it comes to adoption and mainstream acceptance of Bitcoin and crypto. There's really no telling what will happen in the future. I'd like to believe it will eventually reach a bottom and then rise back to new highs. But noone knows.

I will say that your current model and prediction that the low will be about 4k is sort of inline with an academic article that was released about a week ago. It theorized that Bitcoin was 4x overvalued and could drop to around 1,000 to 2,000 dollars. While your estimate was higher it's not all that much higher.

Nice work.

summary of the academic article claiming Bitcoin was overvalued at 8k. https://steemit.com/life/@cryptodivision/research-paper-suggests-bitcoin-is-nearly-4x-overvalued