Take it a step further: permit class permutation at the same time.

(C)(N) > $C2$N1

Where the index in the set N is used to look up the index in C. So if C = {p t k} and N = {m n ŋ} this would swap the place of articulation without disturbing the mode.

If you add this, then I can retire happily and not write klank at all, confident that you've got all the bases covered, and it'll just be a matter of writing a wrapper module for the HT SCA and building a front-end that integrates into Anthologica. (which will be waaaay easier than writing a whole darn new SCA.)

I think the only other feature we were considering (that I doubt anyone's tried before) was attempting automatic syllable break detection.