|Hi from the Critique Club --
What I like: focus, clarity, and lighting are all outstanding in this shot. You did a really good job, technically.
What could be better: A couple of your comments were spot on IMO. A tighter framing of a few blossoms (? whatever they're called...) might be a more interesting shot. This would also take care of the narrow DOF, as you'd be focusing on fewer subjects. Don't get me wrong -- the DOF is great and I'm jealous 'cause my attempts at it always stink.
And, as someone else mentioned, for the "fill the frame" challenge, you'd probably do best not to leave a blank corner in your photo.
Overall, a very nice shot.