I don't see any obvious problems with color on any of them. Here are my thoughts on the motives:
1. Not sure about the rope, but Dana said this one had the best shot so I guess it's okay.
2. More centering than motive, but it looks awkward with the body of the plane on the right side of the image. I expect it would get a Centered rejection.
3. No problem with motive here.
4. This is a perfectly acceptable motive and shots like this seem quite popular. I might try to bring the runway lower in the frame to emphasize the mountains more instead of the empty space at the bottom. Maybe you could also crop tighter since nothing to the right of the windsock (that I can see anyway) is obviously aviation-related. If it's part of the 'airport' though I guess you could leave it and explain that in a note to the screeners.
5. I believe this would be a motive rejection because of the taxiway light in front of the wheel.