Ok, one, I'm not sure how he's going to continue the development of side girls past the pregnancy/children point, and two, if that's the case, the only thing left on the table will be the main story development, which, unless it rounds out very quickly, will make up the majority of remaining content.
Basically, it's the distribution of content going forward which I'm worried about. I am making some assumptions, but it seems the dev may have focused too much on rounding out the side stories before developing the main story far enough.