Thats some real nice stuff man, i really like it ^_^ the painting is superb, so's the scene =0, the colours you've chosen all work really well, and i must say im glad you decided on red instead of blue, it really warms the picture up and makes it much more attractive. The pose is great, along with the composition its also nicely detailed like the bandage of the leg which really adds character. However, i still got a few little crits for ya... some are more personal preference though:
First, the hands look a little odd for the positions they're in, the thumb on the trigger end hand looks like it only has 2 bones currently, this makes the hand look a bit narrow, also the hand holding the barrel looks a little small, i think the palm is in the wrong position compared to the finger/thumb placement. That bandage you added on his leg looks awesome on the right hand side, really nice texture, but lacks deifinition on the left, its like you completely ignored the colours and texture used on the right and just added shaddow and secondary lighting. I also think maybe the scene's roof is too low for the figure, because im not completely sure that the room and the figure are sitting on the same horizon, to me it looks like the figures horizon looks slightly lower than the rooms, but i cant be sure i might be wrong about that.
As a suggestion, i'd recomend that you look into how the lighting will effect the lineart, i mean, the red secondary light looks cut off in places by the lineart. Im pretty sure you could use the light (hue) over the lineart in places to make the lineart less apparent where you want the light to strike the figure, take a look at some of prometheus's work
http://itchstudios.com/psg/main.php?id=misc2 he doesnt really use lineart, but you can see on edges of certain area's have been painted over using the hue of the light to bring the lighting into effect. Hopefully ive been of some help, keep up the good work man, i love your updates =]