I am not a fan of the first two, they seem childish and almost half done. The blizzard fanart is nice for lineart but it lacks some finer details. Are you practicing your coloring? Something I have found in my own journey is the use of photoshop and speed art. I use to think such things were silly and pointless but they can seriously help you to learn the tech that make up the good art. I would also strongly encourage you to ensure you look up anatomy and lighting. These are the two most common rookie mistakes. You can have all the design and concept you want but if your fundamental understanding of those two things is lacking it will show in your art. Good luck and keep at it.

You wanted feedback from a game point of view, so here is mine. When you are doing concept art for a video game, you need to keep a few things in mind. First, if it's character designs or environment designs, eventually somebody will have to come along behind you and realize your sketches as concrete assets. In order to help them in this, you should try to practice your skills at providing them what they need. Some front and side sketches, for example, in a relatively neutral pose, as well as some sketches of them in action so the modeler can see where the lines and bends should flow. The samurai is a good start, but the crouched pose of Wolverine and the... sexy?... pose of the porn elf mean that in order to get a good read on the character, the modeler is going to need a few more sketches.

Second, color and shading are important. Line art is great to start with, but the modeler will need more to give him a better sense of the form and shape he needs to recreate. Again, of the three, the samurai is the best one here. You could just about set that guy as a background and start pushing verts around, although the darks are a bit too dark to really get a sense of the shape.

This becomes even more important when you are doing other than human-ish characters, as then the only reference the modeler will have to see the form of the character will be your sketches. With the porn elf, the modeler could just grab some random porn elf reference off the web and tweak to suit, but when the time comes to do beasts and animals, demons and ghouls, then he will need you to give him good references.

Lastly, and I know this really doesn't need to be said, but you need more. More sketches, more concepts, more, more, more. A good hiring manager will be looking for someone who can do work to spec, rapidly and efficiently. Someone who can work quickly, rather than agonizing over each individual sketch. You need a good, instinctive understanding of anatomy (both human and animal) in order to do this effectively. If you are always tweaking and fiddling with your anatomy, trying to get this or that proportion just right, then you need to practice more. Throughout the course of development, you will probably sketch the same character a dozen times, maybe more for main characters. At a certain point, it stops being a creative exercise and becomes instead a technical one, and so you need to be able to do the work even when you aren't artistically inspired and floating on cloud nine by the wonderful vision you are setting down on paper. If you can still do a quality and informative sketch of a character after you have already sketched him in 15 different iterations and can no longer stand to even look at him without throwing up in your mouth a little, then you'll do okay.

the image i am going to post next is of a Viera PLEASE don't think i made her half naked on purpose, it's kind of the way they dress in FF 12 which is the version i am going to be using, i did think that she was a little too skimpy so i gave her some armor i liked which i borrowed from assassin's creed. once i feel more confident i will post my original works. but thanks for the feed back, i think i will make a section in my drawings for P-elves. (just kidding)

alright here she is Viera's Creed. on your mark, get set, go!