This is the final diffuse map (Fig.15) and specular map (Fig.16) and normal map (Fig.17).

Fig. 15

Fig. 16

Fig. 17
Final Step
Once the texture is done, I did a few poses, constantly making minor adjustments and taking care with the silhouette and line of action. Once I hit the pose I wanted, I exported the files into Marmoset Toolbag to do the final render (Fig.18). The post process feature is truly a great help as I was able to easily change color and mood, readjust lighting and play around with the setting without having to bringing it over to Photoshop (yet). As you can see the result was pretty much there (Fig.19). The renders were then stitched in Photoshop with minor touchup on the background piece. Here's a higher resolution of the final art piece. (Fig.20).

Fig. 18

Fig. 19
Fig.20
Post-Mortem
Looking back on the project, I noticed a lot of mistakes that I had made. One of the mistakes was halfway texturing; I realized the face UV was way too small for me to paint additional details, or to bake a nicer looking normal map. The hair as well proved to be a tough piece as I had to find a quick workaround to make it look decent, though thankfully I had some guidance. I definitely would love to redo the face and hair one day.
Before I end this article, I would love to take this opportunity to thank all the fellow Gameartisans and Comicon contestants. Big thanks especially to Mashru Mishru, Kyalie, Mask_Salesman, mr_ace, resident22, Arkhange, jocz and FredH. It's been a fun and enlightening competition. I hope whatever I wrote is not too much nonsense, and that you could pick up some tricks. Thank you!
Here's the Photoshop plugin NDO I mentioned earlier, as well the Marmoset Toolbag for those interested. I highly recommend giving it a spin.
http://www.cgted.com/
http://www.8monkeylabs.com/tech/toolbag/