Thailand would have some ex IJN vehicles, US Cold War era vehicles, and then later on, an mix-and-match of Western and Eastern vehicles, US, Ukrainian, and Chinese. It would add a ton of variety overall to the Japanese tree which is mostly indigenous with some local manufactured copies of Western vehicles.
Pakistan would add many of the same vehicles as RoC for China, but some unique Pakistani/Chinese vehicles would be a way to guarantee they stay in the Chinese tree, one way or another. Of course the A-5C is already in the game in the Chinese “tree” as a premium, so a precedent already exists. Even though Vietnam and China would come to blows after the Vietnam war, China still has the Vietnamese T-34 SPAAG. So China could end up as the home for random south east Asian nations/vehicles too. Not that many would be happy about that, but I’m just saying.
Turkey I don’t believe would want to be anyone’s sub tree, especially not Israel’s (even though historic military ties exist). I don’t think they slot in anywhere well, and probably would need to be it’s own tree.
I really think a Red-For and Blue-For tree need to exist. It, along with a big UI change, would really help round out all these additions people want.