I agree, the first shot is a little out of focus (looks like your focus point was the tip of the nose).
When you keep the colors warmer, think about whitening the teeth a little bit. Warmer colors will make yellow teeth yellower. In lightroom this is easily fixed by painting over the teeth and reducing the temperature of the shot just where the teeth are.
On a portrait shot, you can bring out the eyes a lot more too by playing with the brush in Lightroom.
Your D750 is a lot more capable!!! I have a D750 and a 50mm 1.8G as well
Here's an example of what you can do with a bit of editing. Hope you don't mind! Trying to demonstrate. This was just a quick 3 minute edit from your JPeg version. You could go for a contrastier look, or a more washed out wedding look. I chose to bring down the greens a little bit. I think all three shots look better in black & white though.This post was edited by Canadian_Man on May 9 2016 07:01pm