It's coming!
1. Child rearing will happen in the good endings for NPCs, and will be playable. The idea being that you settle down and start a family
2. There will be more events with Gin!
3. I haven't finished events for it yet, but yes, you will be able to impregnate her soon!
4. Plant isn't for much later. It's part of a big route I've got coming up!
And yes, always adding more things!