Welcome to the Player Concepts forum! This forum is a creative outlet for the many talented summoners who wish to flex their skills and have other summoners provide feedback. The goal should not be to have Riot take your idea and put it into the game. The goal is to grow your own ability to design within the creative space that is the League of Legends.
That is Riot's stance on this forum (at least according to RiotAmes). Would I love to see an idea implemented from the community? Of course! But as Katsuni explained, that is extremely unlikely, and making concepts with the sole purpose of getting them implemented by Riot would only be an exercise in frustration.
Personally, I think we should focus on making this an awesome environment for fostering creative thought and sharpening our own game design skills. If everyone's only focused on getting their ideas implemented, we will miss out on the chance to band together as a community and help each other improve.