Cullen has always been very diplomatic, even kind-hearted. I can't see him getting into a screaming match with anyone, to be quite honest. I see him getting along with most members of the inquisition, and if he truly dislikes someone, I can at most see him perhaps giving the person a cold look or speaking very stiffly to them before entreating the inquisitor to see things his way.
So with Sera, like you said, I can see them clashing on an ideological level, but I don't see him disliking her at all, and considering his origins (that of a recruit who worked his way up to his current position in 10+ years), I don't see her regarding him as one of the heartless members of the privileged class.
But, I could totally see something like this happening:
Cullen: I hate to say it, Inquisitor, but we must burn the entire city. There is no other way to close the rift. The fate of all the surrounding holdings and villages are stake.
Sera: What?? No!! You can't do that! There are innocent people still living in those slums!!!
Etc, etc.
Huh Interesting point. I guess I don't know what his actual position will be in DA:I and how privileged it might seem. While he presumably started out as a recruit, he actually rose through the ranks to second in command rather precipitously. If he eventually became a knight-commander, he *might* be considered quite privileged. Particularly given somewhat monolithic and pitiless image templars have, I could also imagine her taking an instant dislike to him. And then him eventually winning her over once she learned how moderate and thoughtful he is (and totally freaking awesome...).
Retour en haut
Hmm...
Maaaybe if we don't romance either one, they go for each other?? *ducks*
Everything seems (to me, anyway), to point to these three as being actually really important to us. And this pleases me. 
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