If the Z8 is what I expect it to be, it looks to me as a continuation of the D700 - D810 - D850 lineage, all large, "physical" cameras that according to Nikon tradition could double as a chair or a weapon, whatever needs you may have. To me, the Z7, as good as it is, isn't it. That is more like a D750 with more pixels.
I consider retiring within the next year, at least halfway (for the second time), and the question is if this would be a good retirement camera, one that I could bring everywhere to enjoy pixel peeping at a hitherto unknown level. Maybe even taking a good photo now and then. The alternative would be something Panasonic, even staying with the MFT setup that I currently use. On the other hand, one only lives twice (Or so it seems, One life for yourself, And one for your dreams), so why not use the same camera in real life as in my dreams?
There's space in my Billingham. We will see.