Luce

It's not that Luce wants a position of leadership. He simply knows that he has all the characteristics of one and, furthermore, is the best choice. Raziel has made it clear he wants no involvement in running the clan, Azael is too focused on his Watchers at the expense of all others, Gabriel prefers a more behind the scenes role, Haniel doesn't want to lead, and Raphael is no fighter and so can't be expected to understand what means they must go to in order to protect themselves. Michael certainly has the heart for it but not the experience. The little pearlcatcher doesn't know this world as well as he thinks so Luce is saving him from himself. Michael would crumble under the pressures of leading a whole clan. Really, Luce is the best choice. You'd vote for him, wouldn't you?

The Battle of the Terrace is a prime example of why a proactive approach to threats is the best approach. If the harpies had never been allowed a foothold in the light domain in the first place, then none of those events would have occurred. So many lives would have been saved (and Michael's would never have been endangered). Luce made sure he drilled the warriors in the knowledge that they must strike first and strike hard. Azael understands, but somehow Michael doesn't seem to grasp the reality of their world, despite having experienced it first hand. He still thinks peace is an option and that their highly trained group of warriors should only be used as a defense. Ha!