I wouldn't start by doing it by law and regulation. I'd start by doing it by incentives to political parties to run balanced slates of candidates. Then, if they failed to respond within a certain period of time, I'd say that maybe we should follow the example of other countries and make it that there has to be fifty-fifty on the roster.
I would go to that reluctantly. On a lot of these things, we're asking ourselves if we trust politicians and political parties to fix some of the malaise and the problems, or do we need a set of laws, regulations, and institutional changes to do things that they wouldn't do if they understood what the country needed, things that are against their self-interest.
I'm saying I still have enough trust in politicians and political parties that I would like to see them do it themselves, rather than give them the institutional quick fix that some people may promote.