One question that's just occurred to me is this: What does Iris have to do with the games?
I have an unfinished theory that could answer this, but I'm not too sure if I'm right or not. First of all, we know that Iris is like a feral character (in other words, it's as though she's been brought up by pokemon, hence why she acts in an abnormal way), but in one of these trailers, we see N with a lot of pokemon, so in a way, N could also be feral. This could explain why N wants to seperate humans and pokemon, but because he seems to use pokemon himself, the hypocracy could be countered by the fact that he has closer connections to pokemon than humans, and that he wants to be the only "human" to join the pokemon.
A general trend seems to be occurring throughout the plots of each main series game - that is, all the games' villains want to get their own way and destroy (or disrupt) humanity. So in a way, N is doing this - he wants his own world, which in turn raises the question: what does he plan to do to humans in order to complete his perfect world? I'm guessing he wants to "talk" to the pokemon in order to create an army to destroy the human race, or at least something similar to that. Iris would be affected by this, because in the anime she will be a protagonist, but in the games, she would be torn between the human world and the pokemon world, which is where she seems to belong. [/stupid, rambling theory]