I'm gonna jump around a little bit.
Okay, his perspective for me is like this: T'Challa, as the new king, seems to be trying to maintain the status quo and honour the traditions of his father's rule, which were basically about keeping to yourself and taking care of your people before anyone else (kind of a #WakandaFirst deal, if you get my drift). He's trying to live up to the standards that came before, and then you have Killmonger coming in and saying "No, no. Do something radical! Show the world we exist!"
T'Challa is definitely changed, yes.
So this is where my argument for IC falls apart a bit and is why I think it's a bit underdeveloped. In the OS, I'm near-certain that it's a symptom/response of Control and Uncontrolled. You have SO MANY characters basically saying "these people around the world are being oppressed and punished, we have to give them weapons to liberate them". And while that symptom/response will be shared in the Steadfast IC, it just doesn't make sense to have two doses of that exact same appreciation.
But that whole "let them know who we are" thing REALLY feels like the perspective that's challenging him. I can't think of an alternate influence perspective. Might try and catch the movie again this coming week.
I think Nakia is only IC until Killmonger turns up (one or two scenes). Everything after that, Killmonger is IC/RS.