1st image, there are three points of interest, the hands, the sword tip, the face. The eye does not follow from one to the other very well.
There is a tangent point with the breast plate and the rear arm.
The stance is a bit weak. The arm hides the torso, the hair hides the face, the whole thing is wobbly. No line of action.
The belt could probably be lower. Belt at the hips instead of at the waist.
Edit:
Used a reference for the chin shape. The rest was me just moving things around. Also, I like faces, so I spent some time there. Pose is meant to be casual dangerous. Still needs lots of work, but you get the idea. Argh, the neck shadow needs to extend to the armor. Probably could look angrier too, but I wasn't sure of the mood you wanted.
See how the arm links to sword, which links back to the face. It keeps the eye moving around where you want it to go.
2nd image, neck anatomy is a bit weird. Lighting on the radiator implies a sharper angle than the person's shoulders. Controller needs more emphasis, face could use a stronger expression.
Overall these are rather nice.
Hope this helps,
Tourist