I find that the size of my old Leica M lenses are the perfect size for the various Sony mirrorless camera bodies I've owned over the years, from the NEX 5N to the A7RII. I've been hoping either Sony or Zeiss would come out with small lenses similar in size to my Leica M lenses, but they seem to be going the opposite direction and going bigger instead. I'll stick to using my old Leica lenses until someone comes out with lenses that are small and compact, yet offer the speed and optical quality that I've become accustomed to with my old Leica lenses. Auto-focus and state of the art glass would be nice to use on my A7RII and A6000, but not if one modern lens is taking the space of three of my old Leica lenses in my camera bag.