Feel a bit silly with this post but I'm having issues with focus on my new D7200. I went to a zoo the other day and had a LOT of out-of-focus pics. I found it very hard to get a centre weighted focus point that stayed put! Admittedly I was shooting everything from snakes to birds but I would have liked more control over the focus. Out of 314 photos, I kept 68 (for various reasons.
I strongly favor single point focus too, used for essentially everything (I don't chase fastest motion though). I do like to choose my own focus point, like on the eye of the subject.
See AF-S and AF-C in the manual.
My first suspicion about out of focus problems is always on AF-C focus mode. All manuals clearly say that AF-S is for stationary subjects, and AF-C is for moving subjects. So I use AF-S.
AF-S locks focus and exposure at the half press. At default priority, the shutter cannot activate until focus is achieved.
However AF-C continues with focus following motion as long as half press is held. But manual also says about AF-C "At default settings, shutter can be released whether or not subject is in focus (release priority, page 276)".
So in practice (and at defaults), AF-C triggers the shutter first, and then hunts for focus later. My thinking is it should be the other way around (which AF-S default does).
So (my words) if using AF-C with X frames per second of continuous shutter, the camera might find focus on the 2nd or 3rd image. That could work, if willing to discard the first one or two frames. Or if you are willing to hold half press a short while so it can focus, before jabbing the shutter release.
But AF-S (at default priority) will not release the shutter without first being in focus.
This seems pretty important. I would call it a plus.