Preparation for Book #2: Roughing out the plot

While I gather my notes for Book #2, I'm also beginning to muse on the plot. It would be false to say I don't have a vague idea of what will be happen in it. I have lots of ingredients:

1. The original inspiration - core scenes which have been in my head since the very beginning.
2. Since my series of books is designed around an exploration of the world: an itinerary, which for practical reasons will be based on my own travels though there is definitely room for flexibility.
3.  Since the series is also designed around an exploration of human culture and history: a range of themes to cover. I've already researched most of the ones I intend to use though I may add more if the plot requires it.
4. Stuff inherited from Book #1, not only the main characters, but the inevitable development of the situation on which Book #1 ended (I hate cliff-hangers at the end of books, but I still planted a lot of what will eventually turn out to be foreshadowing).
5. The knowledge of where I want my characters to be by the time I hit Book #3.

That's a lot of information, but it's not a story. What I hopefully also have is more experience of what I need to turn it into one, and a minimum standard in the shape of Book #1.

Right now, I'm messing with the bits, sorting them, fitting them against various plot structures, diving into my bag of stories and mythologies for anything that might be useful, pinning bits together when I detect resonances between them and so on. It's a bit like building Frankenstein's monster: at the moment I have one leg and a head and a terrible feeling that I might end up having to sew them together for want of anything else. Eventually, I need something that looks fully-formed, smooth and inevitable. It will take a while but I do have the definite sense that it's going faster than Book #1.