Never

The pose and expression in this image are excellent. There's a real sense of dynamism here - she's caught in mid-movement, and the strong, slihtly converging lines of the wall help direct attention towards the woman.

I think the imiage could use a little more breathing space on the left, top and bottom. It would help move the face and torso of the woman back closer to a rule-of-thirds grid (see here), and it would allow some sky around the top, leftmost stone. It would also help contain the strong diagonal line of the sword by giving a little space around the tip.

More importantly, I'd also be inclined to add another light around the front of the figure. Not necessarily a strong one, but perhaps a moderate-intensity diffuse light or IDL softbox.

Two reasons for this. First, the image appears very dark on my monitor. While the darkness around the doorway is effective, the woman also seems quite dim. (This may be an issue with my monitor.)

Second, the unfeasibly large sword (love it) provides a very strong diagonal line, and is one of the big impact elements of the image, but at the moment, the blade is cut by the shadow of the shield, and the hilt and guard are obscured by the shadow of the woman's body.

I think these two relatively simple tweaks - a bit more space on the left hand side, top and bottom, and an extra light round the front - would help turn a good image into a great one with very little extra effort.

As a final refinement, consider adding some reflection (either image-based or raytraced) to the sword blade to make it really stand out.