Introducing a "pregnancy" mechanic would imply a somewhat different type of gameplay—we don’t plan to develop the game indefinitely, so we already have rough ideas on how to wrap up the story, and it doesn’t involve such long time spans.
I might not have fully understood the hardmode part—I thought you meant romantic/sexual relationships. In our card-based roguelike, we have difficulty levels, and we’re actually planning to expand it soon with new enemies.
It’s hard to talk about "realism" in a game set in a magical world with wands, ghosts, and spells. We’re aiming for a lighthearted, humorous rom-com with some serious choices that may affect the characters’ story endings.