Hey Jay,
850mm? I really like the BG and contrast of the day lily colors! I think a slightly better angle, w/ a bit more stem and perhaps some of the top petal. Turning the flower some or reposition ever so slightly, can have a big impact. The center looks a bit bright.....but not overly so. That turn may have also allowed a bit of seperation in the stamen from the leaf.....just a few things to keep in mind in the field!
Jay, I think your colors and BG are lovely. I do agree that the composition feels a bit off though. I also want to see a different angle and a bit more of the right side included. I GENERALLY go with either cutting all the petals off or none of the petals off when I compose because I find these half in/half out petals tend to leave the image feeling "unbalanced". Again - this is just a general rule. My suggestion would be to compose with all the petals and a bit of the flower base/stem in the image and then crop to your liking.