A bit more progress: here's where I got to today:
It's pretty obvious which bits are sewn together already; nothing else is carved in stone, which is to say that I am moving these chunks about all the time, so what is on the left now may end up on the right, what is at the top now may end up at the bottom.
I started off thinking of this as a quilt to be made in columns (I've done that before, but things always veer off at some point). Last time, looking at this collection of bits and half-bits I started wondering whether I might make a central block with all these and then use that as the centre for a more medallion-based quilt.
Now I'm somewhere between these two ideas, so we'll see where that takes me. I have to work out next what goes between these columns of birds - triangles maybe.