You really do enjoy breaking them don't you?? ;-) I totally agree about the verticals... the way it is now makes the thing look as if it will fall over pretty soon. The color contrast: unfortunately I don't have a polariser yet for this lens, it is on my wish list (along with alot of other stuff). True, they both were shot in very, very strong sunlight, I know it is not recommended, I even lost some great opportunities simply because the sun was way too bright, and I knew nothing decent would come out of them, but since this was an event for which you had to pay, and I knew I would only be able to go there once, I had the choice to use it or lose it. Showing some context: I left out as much as possible from the surrounding, since that was really ugly, full of electricity cables, streetlights, advertisments, appartment buildings, and big white tents. So wherever possible, I left it out.
The sharpness problem: it is a bit of both I think, alot of the sharpness is lost with the scan, but sometimes I do have problems getting the part of the image that I want sharp enough. I tend to blame the EOS3000, since it has a focussing area of about 3cm wide, and anything in there can be sharp, but with a small DOF, it can be the tip of the nose that is sharp, and all the rest isn't. I really need my Elan II, and I need it very fast...
May I break this one? ;-) You need to align the verticals so that the tower doesn't lean to the left like that (the verticals take precedence over the horizontals in this case). If you want to exploit the colour contrast between the blue sky and the yellow sand, put on a polariser to make that sky a deeper blue. Get rid of the white speck in the sky (is that a UFO or what?). This, as well as the first sculpture, looks to me as if it were shot in very strong sunlight - not recommended. When cropping (whether at shutter time or in post-processing), try not to leave darker bits and pieces along the bottom edge. Possibly show some context, as in the first photo, using shallow DOF. Having said that, if you do show the surroundings, don't show a white house in the distance :-)
Have you determined yet whether the lack of sharpness and the flatness are caused by the scanner, or do the prints have the same problem? Do you scan prints or negatives?