I was playing Samurai Showdown 5 the other day (IMO, it is inferior to 4), when I randomly decided to draw up one of my own characters in a similar art style.

Some references:

I was thinking about animating an idle state or something, but I wanted to make sure everything looks right before I continue. Unfortunately, I know not everything looks right. The stance I chose places the left arm and shoulder in an awkward position that still looks wonky to me. I've also redrawn the arm muscles several different ways, and they never come out quite the way I'd like. I have a couple ideas of how I might improve them, but I'm not certain whether they'll work out, so I thought I'd go ahead and get some external feedback.

I probably need to work on the rest of the picture as well (I just noticed that I even missed some of the transparency on the background...), but I'm most concerned with the arms and muscle structure right now. Thanks for looking =).
Something seems a little strange with his left arm. I can't put my finger on it though. Other than that, it is really good.
Damn, Raven, you've got some skills. I think you pretty much nailed the cell-shading style of those refrences.
Your proportion is good. I thought the head looked a bit small, but I checked it:

And the body is correctly about 7 heads tall.
As far as the arm goes...I wasn't sure whether you were going for a rigid hold on the sword with the arm away from the body, or a more relaxed hold with the arm crossing but against the body. Here's a quick edit on my imagining of the second position:

The arm will have a bend with the curve of the bicep (maybe not my bicep, but definitely his) if it's held against the body. You'll also have to squeeze both pecs up a bit to accommodate the shoulder rotation. I think I may have darkened the edited arm too much there, BTW.
If it's the first position I mentioned with the elbow and arm away from the body, I think you'll still have a bend but the upper arm will be pointing the elbow almost at the viewer. The sword will have to be closer to keep proportion if that's the case.
I dunno. My two cents.

Anyway...really impressive job.
In response to TheMonkeyDidIt
Thanks for the suggestions. I think you were right about the problem; initially I had the sword further back so the arm needed to be tighter, but I shifted the right shoulder and moved the sword up and over a bit, but I just didn't rethink the left arm's position. I bent the arm a little and fixed the left pec up. I'm still not clear on muscle structure, but I'm willing to settle if it looks good enough.

Also, I tilted the sword up because the original intent was that the right hand would be poised over the handle to unsheathe the dagger it houses. Before and after:

Any other comments or suggestions? I'm fairly happy with it now, so I may try animating it this week if I can find some time.