First, why are you not going direct PEK to NRT?

The big question in this routing is PEK. Will it fly on time?
If it doesn't, you are going to be in trouble.

They will not interline Air China with Air Nippon (last time I tried) Which is the reason why we always took MU on both the domestic and international leg.

As for KIX, its a smooth operation. I have never had to wait more than 15 minutes in a lineup for immigration.