Nice stuff, you seem to be doing quite a bit of shooting! Just gonna chime in on the optics part of the discussion.
Higher grade glass generally lets you shoot in conditions where kits lenses would not produce comparable results. Otherwise, it's just as good for everyday photography. There would be no comparison if you has the Zeiss 21mmD vs. a kit lens and had light blasting into the glass.
On skill...
I know people who do have the expensive equipment, and no skill....and don't have the eye to see that what they produce is mediocre at best. As Cricket said, here's so much to be said about the person behind the camera.