I had a 16-85 on my D7000 and really enjoyed that lens, it had all the performance I needed packaged in a very nice and useful focal length. On vacation, family get togethers, and general photography, it was the only lens I needed. I also had a 70-300 which basically never came out.
I had borrowed a 24-120 for a week and used it on my D7000. It too was a very nice lens, but I did not find it as useful as the 16-85. 36mm isn't that wide and there we a few times that week that I just couldn't get the shot b/c I really needed a wider focal length. Also, it really is considerably heavier / thicker than the 16-85.
Based on the photo's I typically take, I probably would get a used 16-85. I can always crop the image a bit to simulate a longer focal length (for the most part), but I cannot make the lens wider in post as I cannot add information that just wasn't captured. Also, by buying it used the investment will be considerably less than a new unit and if/when you upgrade to FX the loss from reselling it will be minimized. But that's just based on my experience and what I did. If you tend to shoot on the longer side most of the time, have little use for the wider side, don't mind the bulk, or think that your probability to upgrade to FX is high and near term, then you will most likely enjoy the 24-120 and not have to go through trying to resell the 16-85.