I used every trick I currently know in this pic, and am not overly happy with the sharpness. Played with levels and curves to bring up the contrast.
I sharpened twice, once at about 50% at a .7 radius, and once again at about 50% at a 3.2 radius. I backed off when I started to see oversharpening artifacts, which is where the numbers came from.
There was some color noise in the armpit area of the kite boarder, so I used an artistic effect (paint splatters) on just that little area to kind of smooth out the noise. I also brought up the blue in the sky, which was a very dull grey, to a color that I thought was both believable, and worked with the kite and the boarder's clothes.
I didn't crop it at all, so that cropping was not an issue in the sharpness. I was using autofocus, which worked a lot better on the kite than the boarder.
F 8.0
Shutter 1/500
Focal Length 250 mm
ISO 400
Raw - Bit Depth 16
So here it is, any criticism and comment welcome.