As a former Leica SL and later SL2 owner, and using the super (and heavy Leica SL 24-90mm lens), I understand the size/weight dilemma. I sold my SL2 and lens due arthritic physical challenges to carry it for a day. But I sure miss that high megapixel, full frame image capability. Your excellent S1R and lenses are equivalent in terms of image quality, as well as size/weight. That said, you say you are primarily a landscape photography (as am I), and in my opinion you should be parking that S1R sand lens onto a light-weight but sturdy carbon fiber tripod. That will not only alleviate the weight, but also force you to slow down, compose, and have the absolute best image stabilization possible. I shoot about 90% of my images (from flower macros, motorsports, landscapes, etc.) on an expensive Peak Design Travel Tripod. If I had your Lumix S1R, and didn't have knee problems, I'd keep it and use a tripod for your landscapes images. You may regret getting rid of it, unless to move into something equivalent in terms of high megapixels and full frame (Nikon Z7II, for example).