Y'know what I do like about this new BAMF Cullen? The fact that he's finally willing to lead. In the previous two games he was similar to Alistair in regards to waiting for others to act first and not taking charge himself. It'll be interesting to see this new side to him, I like that he's really coming into his own at last.
He never hit me as unwilling to lead. Quite the opposite, in fact!
He never had enough obedience. Cullen always questions everything, you can see him doing that a lot. He always has some doubts. He questions the way Chantry treats mages in DAO, then in DAII he ponders on everything you say to him, you can see that he's always thinking, "Is this a right thing?" And he's not afraid of actions that may have serious consequences. My favourite part is when he's trying to tell Greagoir what to do, and Greg has to yell at him, "Shut up, I'm the boss here!"
I don't say I agree with what Cullen was demanding back then, because I disagree, but he wasn't afraid to argue with his knight-commander when he though he was right. And that moment when he told Meredith to step down too. Cullen is definitely not afraid to be in charge. He just didn't have a good opportunity to demonstrate his full potential before. Now he does.