Wargaming gave me a Type 59 — the famously overpowered Chinese premium tank — as a thank-you for a talk in which I dissected their game in front of them. It remains my favourite consulting fee ever collected.
The story has a second act, and the second act is the lesson.
Years later they removed the Type 59 from every account, compensating owners with resources and premium currency. The community split along a line you could have drawn in advance: the owners were angry, compensation or not, while the players who had never owned one were quietly relieved to see the terror retired.
The split reaction is the law, demonstrated in public.
Never remove what a player earned or bought. Not for balance, not for cleanliness, not with compensation.
Removal wounds in exact proportion to ownership. No refund converts a possession back into its price — because by the time it is his, it is not priced any more. It is owned.
Who broke it
What I find useful about this one is who broke it. Not a predatory operator. The industry's fair-play champion, once, with compensation in hand, for defensible reasons — and it still cost them resentment they had not finished paying years later.
If they could not get away with it, your rebalance cannot either.