Air coming into cabin when fresh air is on, is working as expected. That is how fresh air works. Apart from that, the cabins are not made airtight because then they can be suffocating and are a threat to safety, that is standard practice in all cars.
As for the ac cooling, I have used it in summers and it does decent cooling. There is a lack of solar protection film on the windows, otherwise it would be even better, but that is the case in all cars in Pakistan. The sound proofing is not ideal though, and can be improved by installing sound deadening material if it bothers you.
FAW, though slowly, is fixing these issues one by one. The steering rack issue has been solved, the audio player has been changed, door rubbers have been installed.