We don't have this duck in Michigan, so a pleasure to see it. I suspect they are difficult to expose properly because of the mix of very dark and white. Looks pretty good in this one.
On my monitor, the eye is just a bit soft. Perhaps some selective sharpening there would bring it up without inducing much noise in the darker areas.
It looks really good to me as posted Trey, you got the nice sheen on the head and the eye looks pretty sharp to me. It's a lovely shot, if anything I might try just a bit of highlight adjustment to see if I could bring down some of the brightness in the water and the whites on the side.