Theorycraft Alternative Rune Setups for Champions

I would love to hear some interesting new ideas for new rune setups for every champion. I am a player with over 560 champion mastery points. My champion pool is big enough that I can understand the workings of most champions kits and what makes them tick. If you have an idea for an optimal rune setup for a champion, whether it is as specific as a Gold 3 Mastery 5 Kled playing into an Illaoi, or as generic as say, optimal Ahri Runes, I would love to hear and discuss what you have to offer.