Upload & Sell: Off
The DX/16MP game is probably best solved with a D800 (has 16MP in DX). But it is not on your options list.
The biggest "drawback" of FX cameras used in DX mode is the viewfinder. Unfortunately, the remainder of the frame is not blacked out to facilitate framing.
I guess the framing is done later by cropping.
If you intend to continously use the D600 as DX camera, consider the D7000. But ...
The better all round package (for me) is the D600.
Wildlife-long-lens photography probabely is about 25 % of my shooting. If I got the D7000 I would keep the D700 for FX and my Zeiss lenses from 21 to 100 mm.
If I got the D800, I would sell the D700. With the D600 I am not sure whether it could replace both the D700 and a second body D7000.
With regards to your D800/Zeiss comment. Is it your "thinking" or build on experience?
I am not talking about resolution or sharpness. Sure the D800 is king there. I have seen many images with adorable detail. But ( and this really is a subjective thing), D800 images look kind of slick to me, almost supernatural, even artificial in a way, and for me they somewhat lack character. I do prefer the more "gritty" feel of a D700 image. Good old D700 (for me) seems to transport the emotional content of an image better, have not seen many images yet from the D800 which cought my attention in that respect. It might have something to do with the OOF rendering, I don't really know.
Personally, I haven't come accross any situation, where the D800 images were worse than the D700 photos. The majority of my D800 photos is visible better (technically seen).
Can't ignore the fact, that the newer sensor is able to capture twice as many photons than the predecessor. (Shadow recovery).
D800 images certainly are better in a technical sense, the 3fold resolution is just overwhelming, no doubt about that. And shadow recovery is stunning, as far as I can tell from samples. Don't want to question this at all. The D800 certainly is the right choice for landscape, macro and anything else that needs detail. Still, I am not sure about those moody Zeissy bokeh shots I love with the D700 but have not seen as yet done with the D800 (but will gladly be shown to be wrong).
Second point for me is the higher resolution and its impact on USM. With the D800E, i am desharping my images.
are you saying you are applying blur
Together with downsampling the image is more natural than a smaller res image where USM is applied.
I can imaginge that.
I still wonder where the D600 stands between the D700 and the D800, I guess much closer to the D800.
It seems to share the amazing shadow recovery (your jeep images! ).
For my intended use as a "long lens extender" for shooting wildlife the D800 would certainly be the better choice. I am not sure I'd want to sell the D700 to finace it though, also not sure I want to haul around two bodies of 1 kg each. The D600 would be a compromise of sorts, but might not be what I expect on either end of the range.
I guess I need to see more images with both D800 und D600, especially with Alt lenses and my beloved Zeiss lenses.
I am not in a rush, but want to be settled next spring.
thanks for your insights Andy! ...and am looking forward t o more pictures