How to Kill a Champion (Idea for World's)
The losing and winning team in this year's championship should impact the entire league. The 5 champs used by the losing team should be disabled for all league matches for a set amount of time. I am hardcore so I would suggest the whole season for the duration. Knowing how much people might whine, I would be satisfied with a couple days.
This is a good way to bring balance to the game without endlessly nerfing champions. This eliminates 5 champs favored by the pros.