I have that lens, the hd 70, and it makes a very slight clicking sound when I shake it. This is when it's focused to infinity, I guess it could be because the aperture lever is not engaged as when it's on the camera (?). I am fairly confident my copy is in good shape and this is normal.
I can't see much difference between the left and right sides in your examples btw, especially in the one with the building it might just be the difference in how bright the sky is. But there are some tests for decentering that you can do with just a computer, for example:
Photozone - Do-it-yourself centering sanity check - Just Talk - Just make sure the camera is far enough away from the display.