I finally made this, and it turned out really good. I added 6 Thai dragons, but that was all that I changed, just to add heat. The recipe has cumin and caraway; others have had an equal amount of coriander, which I might like better, but that was way back, and I'll have to make a batch with it, to compare them next to each other (friends like it when I make things like this in excess!).
Here are the ingredients for the harissa:
And here is the finished harissa: