These days, I'm slowly exploring the features and image quality of my D500. I gave up on processing wiith the awful NX-D and have run the D500 NEFs through PhotoNinja instead. My version of PN (1.25) does not directly support D500, but apparently does just fine with a little help in terms of colour profiles. I have compared the output against results from the last version (1.34) that claims to support D500, and difference is frankly negligible.
Some of the lenses used with D500 produce very pleasing output. I already mentioned the old 17-35/2.8 that balances almost perfectly with the D500, and the same goes for the 20/2.8 AIS (CPU-enabled). I used the latter extensively of late.
Here is an example of the D500 combined with 20/2.8. Hand-held ISO 200, f/16, at the near limit. Subject is Cinnamon Rose Rosa majalis, a low-growing rose species native to the Nordic region and adjacent parts of Russia.
Full frame, then 100% crop. No sharpening. Not bad for a DX camera in my humble opinion, despite a possible substandard development through PN. The 20 does a good service on this camera, as it incidentally also does on the Df.