So far people who checked the gender ratio of their followings (using one of the existing solutions), were most likely surprised (that it's so biased).

Assuming that, I'll tell them to open their following list, unfollow some of the group they're already following a lot, and follow more from Twiverse and its categories, or if the category isn't there, follow intentionally themselves.

it'll balance it up. That's the route I went and now I have a relatively good mix. I can iterate again, and do that again, but this time using Twiverse.