Karnak, I think there is a 'wide European and American fan base" because the plane is good, or at least because it was good in Warbirds and Air Warrior. We've got the same 'community' they had, if it was a 'world-beater' in there people will expect it to be one in here. That is why there is such a 'wide fan base' for it.
I'm most likely not going to fly it much. Does it deserve a place in AH? Sure, it was on of Japans most important planes. Do the Ki-43 and Ki-44 also deserve a place? Of course. They were at least as important in Japans "war effort" as the Ki-84, and they don't have a 'wide European and American fan base" why? Because they'll be Hangar Queens.