Interesting thing about Japanese aircraft to keep in mind when considering the dull, pragmatic aspects of non-Japanese users is that they were made very specifically for the Japanese. My father and I were discussing this recently in the context of one of our hypothetical "best of" scenarios.
Japanese aircraft were incredibly high performance for their day, the equivalent of most Western designs. This is even more incredible when you look at the hp their engines produced and their all up gross weight. How did they manage that? Well, as they say, "there's no such thing as a free lunch". Japanese design philosophy eschewed such "luxuries" as self-sealing fuel tanks, armor, and basically anything else that prevented the aircraft from becoming a ball of fire if anyone dared to light a cigarette nearby. They had almost zero (no pun intended) ability to absorb enemy fire.
Does this mean that they're totally unsuitable for combat? By no means. But, if used by the British, Australians, or almost any Western military, they would be brought up to Western standards with such protection. They still would have been comparable, but you have to factor in the speed, altitude, and range penalties that would most certainly be brought upon by these modifications.
I didn't mean to say these are totally implausible, just that they wouldn't be as "zippy" as the same planes in Japanese service.
Anyway, they look great, so by all means continue!
Cheers,
Logan