If you're looking for manga similar to How to Colonize Space, you might like these titles.
In the Milky Way galaxy there are many gangs vying for control of the galaxy. Our protagonists Sora Hidaka and Fendy Ecapipo of the Vacca Gang are sent out to investigate a monolith mine that is reported to be run by a "hustler" who is exporting weapons made using the monoliths just outside of Vacca Gang territory in neutral space.
In the future, conception is illegal and fetus production is a privatized affair, occurring only in designated facilities. Any fetus found to have a defect must be destroyed at all costs. During this time, a young woman named Ebidani discusses the follies of her relationship with a doctor...
An accident leaves Taishi stranded on the lunar surface, unable to return to Earth. A girl helps him in his despair, but he is oblivious to her true identity.