Was Oskar Barnack the best 35mm camera designer of all time?
Hard to say. Considering when the Barnack Leicas were designed, I'd say he's near the top. But what about the guy who designed the Nikon RF cameras? And the Nikon F? Or the Leica M series? There are so many good cameras.
there were other 35mm cameras before the leica--there was an agfa tourist or something like that that gave 100 shots per roll, Richard made a stereo camera that used 35 -- barnack's design, however, was the first really practical one, his ergonomics were perfect, which is why the basics of his design are still used today.
You joke. I know you know the Rolleiflex is 120/ 6x6. Barnack was one of the first 35mm designers. The designer of the Ihagee Kine Prakitca is in the running too. Modern cameras are still based on his design.
I have a Leica IIIc (1942) and have been using it as my primary camera.
I really enjoy my Leica II and IIIc. I use them regularly. But IMHO the Contax II and IIa were easily as good as the Leica. And the Contax IIIa is certainly one of my all-time favorite rangefinders. Except for the misfortunes of war the results between these two companies could certainly have been different. Though I do not mind it, I do believe that Zeiss Ikon would eventually have had to resolve the dual lens mount issue but that could easily have been done.
But, I still think that the Japanese would have prevailed in the end.