Beautiful shot. I would add a touch more exposure to it. Lights seem a bit dark. Surprised you used f6.3. Something with such a large DOF, wondering how a smaller aperture would have changed the image. Like an f16.
Its much better.
Second edit is better. You also will have much better results with the D7100. I started with the D3100 and moved to the D7100 so I know what you have grown into to.
Thanks Steve, give me a shout if you fancy a trip out to take some more shots.They are great pictures @Lee532
I really like the sunset shot!