Some D600 + 24-70 f2.8 pictures. Is that IQ expected?

In short, there does not look to be anything wrong with the camera from what I see. Any "Image Quality" issues appear to be directly related to improper settings... high ISO and over exposure, and maybe the white balance could be better.

Some of this could be improved to some extent by RAW processing, but you'll get better results using appropriate exposure and ISO settings.

--
\~K