Thanks for all the comments and input on how to settle on a project. The last couple of days have seen my Libran trait of indecisiveness hit an ultimate peak. I started off the weekend wanting to work on the pregnancy book, changed my mind to Truck of Luck at lunchtime, then back to babies later on in the day. Yesterday I did some plotting for the baby book, but today I've been plotting Truck.
I'm wondering if the best way to handle this is just to plot both, start writing both, and see which one wins. I'm almost certain that one will take the lead. At the moment I think Truck is winning. I've worked on my characters more today and they're feeling a lot more three-dimensional now, and I find that always gets the story moving properly.
We can but wait and see!