30 second exposures are looooong exposures, and when there's a bit of wind going that pushes the clouds forward fast, you will get the clouds blurred, of course. The same happens with the surface of windswept water: it will no longer look rippled but foggy. Blurred. Too much motion there for the length of exposure time for things to stay sharp. I really like the effect here, for that is the passing time as opposed to the city staying still. Well done.
Only nitpick for me is the wide open aperture, rendering each and every light source as a big blob without any definition, but that's about all. The cloud movement would not have shown that well with a smaller aperture (photos would have been darker), unless you had gone to bulb exposure, of course. That's something you might want to try next time, maybe? Smaller aperture and bulb exposure?
first two are nice (great colors) but like said, a smaller aperture would have given you less blown highlights and nice starpatterns in your (street)lights. don't worry about your photo being a bit dark afterward, you can always crank up the clarity in photoshop in post-process.