You can tell Finn's worth as a leader by how he's not trying to raise himself up by pushing others down, even if those others happened to be his opponents temporarily. He's trying to raise himself by working harder and smarter, and if others do the same, he recognises it. He sticks to his own principles, but can also recognise other people's principles, even if he didn't agree with them. Loki familia is lucky to have him. But then again, since Ais is Bell's idol, it makes sense for Ais to have a solid (current) background like that, as opposed to Bell's own, highly volatile situation, which obviously suits the main character (the main character of the parent series).