Ive organized all code I had relating to this subject in a github repository. That should facilitate shooting around ideas. Ive also added more documentation and structure to make it easier to see what is going on.
Hopefully we can converge on a common vision, and then improve the documentation and testing to make it worthy of including in the numpy master.
Note that there is also a complete rewrite of the classic numpy.arraysetops, such that they are also generalized to more complex input, such as finding unique graph edges, and so on.
You mentioned getting the numpy core developers involved; are they not subscribed to this mailing list? I wouldn't be surprised; youd hope there is a channel of discussion concerning development with higher signal to noise....