But if I had a hand in the choosing process, I'd choose to find some other artists. There are better out there. Check my PM reply.
I feel the same way but I didn't feel comfortable saying it before. Now that someone else has opened the can worms... None of them really feel right to me. Elements of each one work but each sample on its own lacks flavor. I like the drawing in one, the composition in two and the colors in three.
The most important thing (at least for me) about a graphic novel is how the renders enhance the story. The panels are usually cinematic and emote to the reader much more than the dialog and what is happening. It must also suggest pacing, tone and the emotion of the scene. For example, remember what I said about #1 where he is ripping off the door? It should have been drawn with the "camera" looking up at the character from ground level with the door over his head, the other characters posed small and almost silhouetted in the background. This would have enhanced his actions, looked exciting and made the door's obliteration more important. It would have also enhanced what the two female characters said in the next panels. The dialog should also have been dropped to another panel or an inset box of the character's face. I would have also bridged the first box and the action box with a panel showing his hands finding a purchase on the door. I would have followed with a reaction shot from the female character before the other explained about his new arms. And my reasoning... you have set up the action, show the action and then explain the action. None of that was done here.
With this kind of work, the artist and writer are basically creating a movie on paper and you have to imply peril or excitement or seriousness or whimsy with color, lighting, composition and angles. Another example is how the panels are layed-out in relation with each other. I recently saw a very fast paced fight scene drawn in a set of nesting panels. The smallest box showed the main character's face with gritted teeth, the second larger box highlighted his fist, the rest showed the follow through and the initial impact. The last box, which filled the page, was the bad guy being slung backwards toward the "camera" from the impact. It really sold the scene in a way that played up the hero's anger and the result of that anger without using a lot of space to explain what was going on. The nesting panels also worked to graphically portray the speed of the action and the BIG impact at the end.
I guess what I am trying to say is this, drawing this kind of thing is all about nuance and telling a story. It isn't just about drawing pretty pictures. I would try to find someone who could do that... and has some knowledge of cinema. (And if I wasn't so completely covered up right now I would offer to do some samples for you myself. Unfortunately I barely have time to do my own housework these days.

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