I got a sample block worked up, and all went fairly well. No problem with the curved piecing on the tree trunk, it's such a gradual curve. And the block does lay flat, which is sometimes a challenge with diamond piecing! It's somewhat larger than it's supposed to be though, (like almost an extra inch), which I suppose is due to all those stretchy bias edges. But if all the blocks turn out that way, it'll just be a larger quilt, right? I'll see how the next block turns out size-wise and then decide about making adjustments.
So I've gone ahead with cutting diamonds. Slow puttering work, because I'm using bits from my scrap bags, not strip cutting. There are nearly 1000 diamonds pinned into color groups in this pic!