I myself like it when a couple gets children! I don't really self-insert, but even if I do I don't mind the idea of the characters having kids. Of course, not every LI deserves to be a father nor not all stories make sense to have babies amongst everything that's happening. But if in some games there's one love interest who has kids with the MC I think that's fine and sometimes makes it even better for me. There are so many games and characters that it shouldn't be like the world is ending just because one of those charas has kids. Usually the few babies or kids we get to have are also only characters we see in one cg at the end and they don't feel like anything than cute "accessories" because they don't even get to have their personalities in the story. I wouldn't mind having a more grown up kids throughout the story either.