Improved noise levels and specifically significantly better dynamic range
High resolution, blackout-free EVF: probably 5.76 MP or maybe even 9k MP viewfinder, 120 Hz refresh rate (the resolution can be reduced to increase the refresh rate)
New user interface (no second LCD screen on the back like the D6)
As always, anonymous tips are welcome. There is also a brand new Patron page since several readers have asked me for alternative ways to support the site. Thanks!