To be honest i think Relic shouldnt eliminate a faction because u cant find a super heavy Maus like Ubertank for the faction.
Out of my view u need a set of weapons to build a CoH faction like a ranged unit, close combat unit, suppression unit, hard soft counter, hard counter, ect ect pp.
Japan, Italy and France have all those kind of weapons. So when Relic would be interested in those nations there is no reason to kick them out because they dont have any super weapons.
That isn't really the point.
The point is, everyone except soviets, brits, USA and germans used literally toy tanks and nothing that could stand up even to early shermans ever seen the combat/mass production.