Step 1: Go through the projects you're already working on and change a bunch of the characters' first names to women's names. With one stroke you've created some colorful unstereotypical female characters that might turn out to be even more interesting now that they've had a gender switch. What if the plumber or pilot or construction foreman is a woman? What if the taxi driver or the scheming politician is a woman? What if both police officers that arrive on the scene are women — and it's not a big deal?
Step 2: When describing a crowd scene, write in the script, "A crowd gathers, which is half female." That may seem weird, but I promise you, somehow or other on the set that day the crowd will turn out to be 17 percent female otherwise. Maybe first ADs think women don't gather, I don't know.
And there you have it. You have just quickly and easily boosted the female presence in your project without changing a line of dialogue.
I'm sorry, but this is absolutely ridiculous. Firstly, when someone suggests to me and anyone else I can think of that a "crowd gathers", it's a pretty mixed bag: young, old, male, female, alone, in a group.
Secondly, as 2P51 said, men and women do not engage in the same activities in equal proportions. When you think of a battle, you think of a bunch of young men making war - because that's who makes war. When you think of an elegant ball, you think of women, because elegance and gentle Victorian-esque occasions are considered feminine. There's no evil in this, it's a natural selection of activities; it's normal.
The reason saying "A crowd gathers, half of which is female" sounds ridiculous is because it is ridiculous; it's a forced display of hyper-feminism and political correction that anyone with a functioning brain doesn't need as a supplement. Further, the authors of the adventures chose to make a story that primarily consists of males; it's their story and their artistic value. If they wanted to make a universe of only men that breed out of their buttholes that's their right. Nobody can stop you from changing characters in your playthrough, but stop decrying and slandering their work as it is.