The three secrets to PhotoShop are 1. Layers, 2. Layers, and 3. more Layers. I use noise reduction, too. But I ALWAYS duplicate the background, reduce noise (using Neat Image), and compare to see if t much detail is removed from certain areas. Also, using the noise reduction SW to smooth skin is risky since it can result in uneven removal of details. The noise reduction is going to remove only things that look like noise. I'd also recommend against using the noise reduction except to remove excessive noise. All pictures since the beginning of time have some noise; remove too much and the image will look unrealistic.
So now that you have removed only excess noise you need to address the skin. My I rarely do much with skin beyond the Spot Healing brush, but when I need to I duplicate the background layer twice, apply 1.0 pixel (or less) highpass filter to the top layer and set to "overlay", apply median filter plus blur to the lower cop and mask them both in black to they do not show. I'll then paint the median/blur layer mask gradually (<20% opacity brush, 0 hardness) on the areas that need touch-up. Finally, I'll paint back in some pore/eye/lip/eye brow detail using the highpass layer. Fine tune both layers using the layer opacity. This process is also good for reducing shine.
The key to this, and any process really, is selective application using layers and masks.
For the eyes I used the healing brush to remove the veins, then used a hue/saturation layer to whiten and brighten. Again, applied a black mask then painted where I wanted the mask to show.
Same for the teeth but separate since the hue ends-up being slightly different for teeth.
White brush for the catch-light in the eyes.
Another hue/saturation layer to boost brightness and color of the iris. I like to paint in the layer using a very fine brush (2px) using strokes that radiate from the inside out.
The sum of the changes is subtle but important in the overall finish of the image.
