Perhaps it's time to continue Spinsters in Space. Also a sexier title perhaps. The situation is a remote planet, and the only life is benign plants and our four women with the bodies of small teen girls, who can do genetic engineering in the spaceship they've landed. Story wise, it's a lot of freedom!
They've been thinking about developing another girl, and also giving themselves cocks. They've already increased their sex drive. So, a story, with tension and an ending, that's not tooooo obvious or absurd...