It was the only way I could square the contradictions created by Xander being the leader of the pack

I'm not sure any of the others had the capacity to be the leader. Xander always had smarts, regardless of the goofiness. In other respects, they were probably equals. So, I have no real trouble with his being the leader of that particular pack. It stands to reason, if Buffy were going to be the alpha female (as she surely must be were the episode carried to its logical conclusion), then Xander would have had to be the alpha male.