24-70 question

I'd value opinions please on these shots

7d
24-70 2.8L
200 ISO
68mm focal length
f5.6, f4.0, f2.8
tripod

Other shots I took indicate that at the wider angle end of the zoom range the lens is sharp even at f2.8 (OK some diff, but nothing scary)

at the zoomed in end - well you judge. The f2.8 shot is far softer than I expected. Am I being too harsh?

(I've cropped the shots so the files are manageable)