Okay, what you really need to learn to do is change the layout of a skin from the original blizzard one. I'm not saying you just edit the existing one for every skin, but for the skin and the skinning contest I have seen you just use the blizzard layout. Don't be afraid to stick with the existing skin, go out and change it thoroughly so in this case, it doesn't look like the wc3 bloodmage. I painted over the screenshot of the face to show what I mean. Go out and change the cheek structure, how his mouth is, where the light falls on his face. Also I think your glow is too strong. The concept's glow barely falls onto his cheeks.
I like what you did for the bottom pauldron, but for the top one I think you should either see how you can alpha it to be more like the part by his neck on the concept, or play around with it so you can make it look a little less like a little kid's drawing of wings, no offense of course. You might also want to change the color of the pauldrons so they don't look so plasticy, more gold/bronze like the concept.
The mantle looks really cool, leave that.
For the armor I'm not liking the bright red. Try a real dark maroon like what I painted over, and outline that with some gold to make it look like plates. I copied the bracer's design, and I think it would look cool if you did that. I know the chest unwrap is horrible, but it can be worked with.
Try to work on your colors. When you shade with a white like that it makes stuff look plasticy. Look at the colors on the concept's pauldron, how the brighter it gets it doesn't get whiter, but a different shade. Also look how the concept shaded the cape. Beeing able to manipulate colors like that is extremely important.
You don't have to follow my advice, much of it was opinionated, but if you do follow it, don't follow it exactly. Experiment around, no one will do something exactly the same, or have the same technique.