You know, every time I see one of their behind the scenes video I feel that something is off with my champion concepts.
I just can't pinpoint what. It's frustrating.
My guess would be that your concepts aren't being beat up by a full team of people with competing ideas and inspirations. Every champ pod has art, design, and narrative embedded, and that's not even including the gameplay teams, art discipline, other champ teams, etc.
Champions evolve and improve a LOT because of (sometime-difficult) collaboration and the push-and-pull of what different people think is cool or right for the character. I bet if you aggressively chased feedback and tried to incorporate it into your ideas, you'd start to find that missing piece.