edit: I see from your exif data that you're in AF-S a lot of time....try playing around with different focus modes.
The focus points on a lot of your pics isn't directly on the subject.
I have this problem too sometimes...a lot of times...especially when shooting people.

http://imaging.nikon.com/history/basics/16/03.htm
and from the G.O.A.T. photo site:


"AF-S, or AF-single, means that the camera focuses, and then locks.
This is used for things that don't move.
You point the camera at the subject, hold the shutter halfway until the OK light lights, and then move the camera to recompose your photo while the focus stays locked."


"AF-C, or AF-continuous, means that the camera focuses, and then keeps focusing as the subject moves in and out.

This is used for action.

AF-C works great, but on older cameras, only if your subject stayed in the middle of the frame, right under the single AF sensor.

Used with careful selection of many AF points under AF-Area modes, the D7000 can select different sensors to track motion around the finder, while this AF-C mode lets the D7000 track focus in and out to keep the subject sharp."


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