Taking the bottom image as an example, there is a 1ev boost in exposure which is about the the amount the sky is over exposed. The haze seen is not pollution but pretty natural phenomina. The contrast is low due to the haze and also I might guess the lens hood was not in place. Bright out of frame light hitting the front lens element causes contrast loss in the image.
If you were shooting in RAW, all this could be repaired but there is less adjustment range in JPG. Even without the lower adjustment flexibility, I downloaded your small JPG and added contrast, sharpening and reduced exposure by 1 ev. There is lost detail in the high tones but the original RAW data had a lot of recoverable data in the high tones which would have recovered the sky detail and color. You were using Standard PC which does not have much sharpening or contrast. Vivid has more sharpening but also more color saturation, so give that a try and see if your images in those conditions, would be more to your liking.
This image file is pretty small so any adjustments leave artifacts, like the ghosting on the tops of the mountains. With the original large file or in RAW those artifacts would not be there.
The D7000 has many options that are not needed all the time but are needed occasionally so it is not an easy camera to master in a short time. In this case, Bracketing being turned on would have produced one file that was just right in exposure and one under exposed and one overexposed, this one. Just like with your scanning the control panel of the 747, it was really overwhelming when first trying but later the physical scan and distinct spots your scan expected to find them at, is similar to the scan of many parameters that users of the D7000 or any advanced camera learn to do before any shot so there are fewer surprises in the results. With a little more time and some experimenting with the different features, you will be able to notice minor misadjustments or being in undesired modes without even really looking. At first it is work to check everything before triggering the shutter but eventually, you will just "know" if something is amiss.
Good luck and have fun!
Stan
St Petersburg Russia

Visit my Nikonians gallery.

Attachment #1, (jpg file)