I have used the Summicron 35mm and 50mm for landscapes quite a bit. also used the 21mm Elmarit M, but it was not my style of images. Later sold all my Leica lenses and now use the Zeiss ZM 35 f2.8 and the ZM 50 f1.5 lenses. I liked the look of the Leica lenses, but also like the look of these two Zeiss lenses, and the difference in dollars between what I sold the Leica glass for used and the price paid for the Zeiss glass new allowed me to buy a 24MP DSLR to use with my big telephoto lens.
I find that I really like the Zeiss 35 lens for it's look and lack of distortion. awesome lens for the price.
The Zeiss 50 f1.5 is an interesting lens also, but takes a bit of getting used to due to it's focus shift. Once you get that under control, it is a wonderful lens as well.
Regards,
Akitadog