Why hasn’t aram had a similar thought process in mind? Ability specific buffs and nerfs instead of modifiers has been desperately needed for years now and this new game mode is receiving them within not even a month of being on PBE. Just a bit weird to me but hope this idea will be out towards aram if it proves to be successful.
ARAM has started doing this as well recently. Currently the individuals who do a lot of that balance are helping get Arena out the door at the moment, but I expect them to continue doing tailored changes for ARAM in the near future.