Tom
I've only just got round to looking at these. Some very strange-looking vehicles here!
Clearly they were relying on foreign imports until at least the early 30's. And what about the GB/Russian "Austin-Putilov" - some hybrid.
The type 91 and Otsu B look just like how tanks were protrayed in cartoons, or any drawing or film by people who didn't know much about them, during the 30's