Character mistake: In the final scene Cobb's children class him "daddy!" but Cobb's son also calls him "Leo!"
Character mistake: On the Shinkansen train, Cobb says, "I'm getting off in Kyoto." Not exactly wrong, but a moment afterwards they are in Tokyo and you see the Tokyo skyline.
Suggested correction: Yes. He gets off at Kyoto and says "every man for himself." Perhaps this stage of the plan was for him and Arthur to split up to avoid a tail (we do see later that he is being tailed). But regardless of the reason, we see that it is daylight when he leaves the group to get off at Kyoto. Plenty of time for him to be in Tokyo by nightfall.