I've been using org-drill a lot recently. I've already added one feature that I consider vital for this kind of thing (answering by typing!) and would like to add another (some form of Leitner box learning).
But, it seems sensible to fix the maintainership first. Are any of the forks out there active at the moment? If not, I'd be willing to take over the maintainership for a while. Is anyone else interested? Does anyone object? Phil