I didn't opt to get the Z6 solely for the weight savings. I knew with F mount lenses that would be negligible. I will say that the camera with the kit 24-70 f/4 lens *is* much smaller and easier to carry for the day. So from that perspective, as a versatile day trip kit it does fit the bill.
I like the larger focal point coverage (nearly 90% of the frame). I like the joystick for moving the focal points (I missed that from my Canon days) although I think that's in newer Nikon dSLR bodies than I own. I like the in body stabilization (I can handhold to 1/30). The battery life so far isn't a problem for me.
I am struggling with figuring out backlit studio images, but this is not something I shoot often. And I'm only working on it because I read it is a limitation specifically to EVF. It's not something I really worry about though as I don't often shoot directly into a flash.
I still don't need auto ISO though.