C&C per req:
1. I very much like the composition of this image, but the exposure is a bit of an issue. The foreground needs to be at least 1/2 - 2/3 stop lighter. Given the time of day, and angle of the sun, this is a tricky shot, but I think with a little more work in post, you might be able to 'tweak' the foreground.
2. Again, nice composition, but the main area of interest is just too soft and grey. I think I would consider cropping out some of the bottom and increasin the contrast of the buildings at the top.
3. I'm afraid I'm not fond of the treatment here, but that's a personal preference.
Overall, you seem to have a good eye for composition, but you're being led astray by (I assume) your camera's light meter. Each of these images is shot into, or near the sun which causes a huge dynamic range from blown highlights, to solid shadow. Try, if possible, to photograph at different times of day. We generally say that early morning and later afternoon evening (when the sun is low) is the most favorable light, but if that means that the sun is pointing directly into your lens, than try waiting a little while.
Overall, good effort - I'd suggest a little more practice in exposure, and try various metering modes (if you have them) or just experiment by shooting into and than progessively more away from the sun to see how it affects your camera, and the exposure.
Just my $00.02 worth - your milage may vary.
~John