As I began stitching this part, I decided to try a lighter shade for the pale green. It didn't work. It was even worse than the blending into the background that happened in part 2. I went back to the color card. When I chose my colors originally, I had skipped a shade from medium green (367) to pale green (368), thinking that it would make the difference just a little more pronounced. Since the even paler green (772) just didn't work, I decided to go in the opposite direction, grateful that I had that choice. It worked. The new pale green (320, seen a little better in the closeup) shows up much better on this fabric. I will probably go back to part 2 and change it out, but I won't mess with part 1, since those satin ray stitches show up just fine.
Full design so far:
Just part 3:
And here's a little closeup of some of the detail: