The whole dominance thing seems to be terribly complicated to explain. Patty and I have talked about this at length, and it just seems to get more complicated not less.It is more than physical prowess, though that's certainly part of it. The wolves depend on the Alpha for leadership and safety in a world that's pretty hostile. New wolves, without leadership, would be dangerous to everyone around them, and easy prey for darker things at the same time.
The pack functions a little like a military unit getting new recruits. To start with they scare the newbies half to death, and tell them when to brush their teeth, when to sit and when to sleep. Those who can't adapt die. Those who survive become part of the pack. Think about the sort of characters you'd like to see in a military commander, and that's what a good alpha needs. Sure, you'd like him to be tough, but you also want him to be smart, and fair, and charismatic. The kind of person people follow willingly.
The dominance thing is as much about personality as fighting ability. Many dominance questions are solved without a fight, or with only a token fight. For instance, lets pretend that one fine day the wolves all got over their homophobia. Warren and Darryl might well agree to switch places, with Adam's blessing. If a formal challenge were required (I can't remember the rules about that -- Patty set it up such that the top positions required a formal challenge, mostly to insure that the whole pack was aware of any change in rank), then it might be as simple as Warren entering the ring and Darryl formally yielding. It doesn't have to be bloody.
Ben may be a good fighter (I don't think Patty has ranked fighting ability by itself -- she just makes stuff up!), and he's loyal. But would the pack follow him into battle? Could they trust him to put them first, and himself second? Is he a LEADER? That's what makes a good dominant wolf. The pack bonds allow the pack members to strengthen those they support. A perfect alpha has the unanimous support of the pack -- which makes him virtually impossible to defeat. Successful challenges for top positions usually mean that the pack was itself divided on whom to support. Usually, just violence isn't enough to get a wolf to the top of a healthy pack. Remember, Adam was not only wounded, the pack wasn't healthy, which is the only reason Paul had any chance at all.
You can rise in rank through sheer violence, but a pack ruled by an Alpha whose only virtue is his fighting prowess is in serious trouble . . . and probably due a visit from Bran and/or Charles, like Leo. Ben is probably due to rise in rank, but he has several personality flaws that effectively weaken him and make it harder for the pack to support him. Ben is a work in progress -- but he doesn't belong in the top ranks yet.
Does that make any more sense?