Loot after a game, similar to monster hunter, into adding a place of progression
The idea would be to gain loot depending on the enemy champions played against. This loot can then be used in a place inhibited by poros. The loot can be used to help the poros in adventures and the search for gemstones which is what the poros seek.
League consists only of gameplay which is nothing wrong, but implementing some other means with progression would bring new substances and bring new experiences. It too has the advantage that the player always wins something with each game and maybe therefor reduce the toxicity in the game.
The loot would be marks of each champion. Depending of the lore of the champion these marks can be traded in the sea, mountains or grassland for information where the gemstones are, in which the poros can go find them.
There can be different tiers of marks with different chances of getting them.