The charcoal roasted coffee actually smelled and tasted decent, and better than expected. After the initial unknown coffee, I roasted some Gedeo Worka, which I had been roasting the past year. The dry aroma actually had fruit, which persisted into the wet aroma. The acidity was muted but preserved. The body was fuller than the typical Mini 500 roast.
There was only enough for two drinks (v60, 12g coffee/200g water), so the handful of green coffee yielded about 25 grams after roasting.
This is a fine method for observing the changes of various roasting stages. I probably will use a mesh over gas stove to show the uninitiated how easy it is to roast coffee.