New Champion Concept
I was thinking of a new champion that was based around the premise of evolving similar to the monsters that we see in the game Evolve. How it would work is the champion would have to kill X amount of creatures per each stage with a max total of three. Once X amount has been killed they can evolve to a stronger state. When they evolve this would increase the base damage on their abilities slightly as well as allow someone to change one of their abilities. Upgrading an ability is similar in the way to khazix mainly by making the ability stronger in a certain way however unlike khazix the upgrading process would have different pathways to follow and each would add a new unique effect for each ability.
For example if the q was a hurled projectile upgrading it would cause that projectile to either have a larger width and leave a trail of flames behind it or have a much thinner width, longer range and be able to piece through enemies.
I definitely think that this would bring some fun element to league as you can have a champion that you can fit to your playstyle with it.