Profile banners

I was just wondering why we are unable to change the profile banner without having it correspond to the icon. For example, maybe I would like to have the phoenix icon but the tiger profile banner, or I really like the icon from an event, but I want the pulsefire ezreal banner. To go even further, why don't we make more profile banners that are obtainable through special events such as the harrowing, or just have banners that show a strip of champions' splash art? I think this is an interesting concept that would allow people to personalize their profile further without being super difficult to add-on (hopefully!).

What do you guys think?