I doubt a lot of people remember it but there was a system in place in the original BF though it only got to implement a couple of changes.
It was a sort of "player council" that would discuss balance changes with the developers following certain steps:
1. Cards would be submitted to balance changes by community vote
2. If the devs agreed that the card could use a change (based on the Database: Number of places \ Win Rate etc.) the "council" would be asked to submit arguments for certain changes in a secluded part of the Forum
3. The Devs would collect theese changes and propose a