Riot places more emphasis on surface content than on any real depth of content - hence why they keep making new heroes with new resource and combat systems (the 3 ninjas, renekton, karma) while leaving the old heroes on the vine for the most part. Sure they get hit with buffs and narfs form time to time but at some point they have to realize that they can't double the number of heroes and expect the old and new to mesh together magically out of the blue.
Hence, they make this game a more casual game. No new maps since launch, no new game modes, no lan support, horrible chat server stability....it makes me wonder why they place such a heavy emphasis on banning players when they really don't hurt the game more than it hurts itself.