Although I am really excited about the a7 III release, I’m also taken with the notion of uncompromised silent shooting. I love using silent shutter, but don’t want to fret about reduced image quality (12 bit, or banding, or rolling shutter), so my heart is moving back in the direction of the a9.
DR is a big deal for me with landscapes, but that’s already adequately addressed in my landscape camera: a7R II. 13 stops is plenty for what I’d use the second camera for.
My ideal two-camera setup then is a9 + a7R II. (I currently value the a7R II SR app more than the a7R III battery).
That said I still might go with an a7 III...just need a lot more time and want to see user reviews before making a final decision.