This is more of a "for fun" idea and I kno many of you likely won't exactly have much thought or opinion here since most of the community is likely not at this point, but I have recently reached a point to where I am starting to run out of stuff to spend IP on. So, I thougt, "Hey, why not just have it be something entirely cosmetic?" Introducing "Personal Poro", a pet that you can customize and bring into a game with you if toggled on.
The idea here is a player can purchase a pet poro once they reach Level 25. They name it and then use IP to customize their own little pet so as to express themselves. While in-game, their poro will follow them around while they are out of combat with enemy champions. Out of game, perhaps the poro could have a very small chance to fetch keys and/or chests depending on which you need, but it doesn't have to. Pet poros are like a small secondary skin for the user to express their wealth of IP. Perhaps there are some INSANELY HIGH IP cosmetics for a pet poro for those who just want to dump all of it into their little friend. I think this could be an interesting IP sink to League since it's not a system that impacts gameplay at all. It's just a way for someone to express themselves and show off dedication to the game!