Forget what I said before, those cookies were amazing. Once they cooled, they were far better than the wheat version I made. Flavor was fantastic, and texture was perfect. They would have been reall good with nuts added...
One trick I did not mention, because I didn't think it was important: The 1/2 cup butter I happened to melt on the stove, because I was in a hurry, and in the meantime I forgot it was there on the stove, so it ended up as browned butter. Perhaps this was part of the deliciousness?
So, stick to the flour mixture I originally used or tweak it as you'd like:
1 cup millet, 1/2 cup oat, 1/2 cup garbanzo. Oh, and I forgot, I used 3 different kind of chocolate chips. Did I mention that already?