Game Modes, Themes, and Maps

Hey there, Area here. I have been playing League on and off for a few years and have recently begun playing almost religiously. I was just curious if there is a submission system for game maps, modes, and themes similar to /All Chat? I am taking my time to focus on fun aspects as well as balance issues to keep one or two champs from dominating. I have all but 7 champs now and I am starting to look at the games win percentages and see that while there are some clear favorites the majority of champions stay close. I think it would be cool to put forth an idea and have a chance of it actually being used, other than slapping it up on a discussion board or forum, any suggestions for me?

Hoping for a Riot reply, but would like any honest answers from knowledgeable individuals.