Maybe should have brightened it up a little and given slightly more contrast. Great shot anyway, I really like the DOF with the out of focus flowers around.
Nice and crisp on the left wing, but not on the eyes or other wing. Lacks color fidelity. The ugly, dead-looking flower in the background on the left needs to go. I don't agree with the "no spot retouching" rule for stuff like that.
I think that cropping the dead thistle head on the left would have made this a stronger image...cropping as you shot it, I mean, so that you don't lose the tails of the swallowtail...nice light