So what is the suggestion? A quota of female teachers / a quota of teachers from various orgs / a quota of teachers from various minorities? I am not able to go, but if I were, I'd just want to train with some of the best, irrespective of who they were or where they were from.
Something like the AikiExpo is the result of the way orgs train / organise themselves. As such, the event itself cannot really be accountable for the top teachers produced by the various Aikido organisations.