Create a formal avenue for commenting on specific proposed changes
When the U.S. government wishes to implement a new regulation, it typically goes through a public comment period where (1) the regulation is posted online, (2) the exact proposal is detailed, (3) the public can read others' feedback, (4) the comments are summarized prior to posting the final regulation in a relatively short document and (5) the agency responds to those comments. Much of the frustration on the side of the users is due to the lack of transparency in considerations regarding how a champion will be balanced or how new changes will affect gameplay.
This proposal would, I think, lead to less frustration even if not complete satisfaction with the process for implementing changes. Part of game development is communication with consumers. When the discussion is not acknowledged, it is difficult for players to invest their intellectual resources in the game's development.