I may be way off base here but this is my interpretation of what I think you are saying. First off I have to say that I love the image you posted for the same reasons that others have already described.
OK, here's what I see. When comparing your image to the example photographers you have mentioned I see the following differences. (Please accept that I am generalizing and each of the points I'm making may not necessarily apply to each and every one of their images, but they do apply to most and to their body of work as a whole.) You used the word "pow", I will use the word "pop" in my descriptions.
1. Most of their images, especially the headshots have very clean and non-distracting backgrounds. This is expressed in a few different ways, blur, solid color, difference in luminance, difference in color, etc. Whichever method is used, the subject definitely "pops" in the picture and is obviously the subject.
2. Closely related to this is the visual separation between the subject and the background that is evident in most of their images. Even the few images where the background is in focus, the subject is definitely the subject and draws your eye and again "pops" out of the photo.
3. Another thing I see is the vibrance of the images. This also helps to separate the elements of the photos. As the colors are made more vibrant they tend to separate themselves from each other which again adds the "pop".
4. The level of contrast used is also a huge factor in my opinion. Most of their images have a higher contrast tone curve applied. Even the black and white images and those with desaturation applied have a higher level of contrast. This again separates the elements of the image and causes the subject to "pop".
5. The eyes are the window to the soul and are probably the most attractive and engaging feature of each person. In most of their photos, there is a great emphasis on the eyes and connecting the viewer with the subjects eyes.
Numbers one and two are done in camera with the choices you make with regard to composition, background and framing and with the exception of cropping, are set once the button is pushed. Three and four can be enhanced in post to add the flavor you want. Five is a combination, with proper lighting being one part and post processing being the other.
Taken together, these things can make an image have that "pow" you described. As an exercise, I would love to see you re-edit the photo you posted here with these things in mind and see if you can achieve the look you are seeking.
I hope this helps. If I'm way off base it might have something to do with the time. It's way past my bedtime.