More Powerful Custom Tools?
If you've ever delved into competitive Pokemon community on Smogon or taken a look at all of what Magic The Gathering has to offer, you will quickly find that the main meta is not always the only preferred play method.
Pokemon has several tiers of play: Over Used, Under Used, Rarely Used, etc, as well as many side metagames with different rules including monotype (ever pokemon on the team must share a type), Little Cup (all pokemon are first form) and Hackmons (hacks are legal). Some of these game modes are just remixes of regular gameplay, while others add new tactical depth or open things for ridiculous shenanigans like URf.
Magic the gathering has a style of play called Commander, which came to be a lot like League's ARAM. Players came up with a game using magic cards where one Legendary creature acted as the commander of your deck, being summounable every game and creating a theme for the deck itself. Wizards of the coast decided to provide official support for this game, releasing products and rulings for it and now it's one of magic's most popular ways to play. They also have active support of legacy formats and spinoffs like Pauper (common cards only).
These examples were possible because competitive Pokemon is mostly played on an easily modable online simulator, and Magic the Gathering is simply a paper card game where you can change the rules at a whim. If there was, for example, a rudimentary custom map builder, players would VERY QUICKLY find the fun alternative playstyles they want to enjoy that riot has been trying their hardest to find in rotating game modes. Even if a tool like a map builder was so simple as to be laying mere blocks as walls, if players had any control over the rules of the game i can guarantee that amongst the piles and piles of crap, new interesting experiences would rise to the top and gain great popularity. If Riot promoted the most fun maps once in a while, it could do a lot for the league community.
