It is hard to say how much I am willing to spend for now. I know it is a bit too much for Z8 and paying the full price for a 3 years old Z7ii is probably too much as well. I probably be happy to pay around $1-1.5K for a very temporary backup body now until the info of Z6/7iii is coming out and decide for a permanent backup body. Zf spec looks nice for a $2000 camera.
I guess I will have to see the spec of the Z6/7iii before I make a final decision. If the Z7iii is 61MP it would be a good option for me as I can benefit for a landscape, if AF is good enough for at least perching small birds in low light. I plan to have the Z180-600 for the casual trip so I could benefit a bit from the a ability to crop small birds too with either Z7iii or Z8. My main wildlife photo would be only birds.
Thank you vey much for all the comments.
Passakom, It is hard to give specific advice without knowing your use cases and style.
We know you have a Z9...What do you use it for?
We know that you don't want to afford a Z8.
You are willing to settle for a Z6ii/&ii as an interim choice. Maybe also the Z6/7 although most of my experience is with the ii's. I rented a Z7 once and it was as good as the D810 I had at the time, which means it is very good for static objects like birds.
I used a Z9/Z7ii combination professionally for about 18 months, often hanging them from each side using double slings. Somehow, and it surprises me, I was able to adapt to the different ergonomics and capabilities between the two cameras. Now I use a Z8/Z9 combination.
As a personal thing, I do not put too much value into higher-count sensors, particularly for landscape. I have an acquaintance who shoots landscapes with a 36 MPix camera (D810), shooting 2d panoramas and tiling them together in post. He prints wall-sized images on metal. The obsessed can go over them with a magnifying glass and they are glorious. Have an endless sunrise on the wall in your bedroom if you can imagine that. I have shot panoramas of murals on the side of buildings, hand-held, and reconstructed them easily in Lightroom.
I shoot with the Z6ii also and am always impressed with its performance in low light. I also find these lower-count, higher-ISO images easier to process. Sure, you can beat a high-count image into equivalency by pixel averaging and DeNoising, but it's more of a process when you're in a hurry. If there's more light, and you need to crop, then, of course, more pixels can be better (up to a point).
So, I just do not prioritize pixel count above about 45 MPix.
Probably a used Z7ii is best. This would match the image quality of your Z9. Many seem to be available these days as people "upgrade" to the Z8. If you get a good deal, it will serve as you wait for the anticipated Z6iii/Z7iii which will come any minute, as has been anticipated since the day the Zii's first came out.
I would think anything less than full frame would not be appropriate...That involves different priorities not in evidence.
