I didn't just say stuff that would stop the income I also included things that would bring nothing in.
But if you want an example from mech arena's history let's use implants. Originally customizing your pilot sub-optimally was a mistake you had to pay for. Not necessarily with real money, but with resources that are crucial to progression that can be bought with real money. Spend your a-coins wrong, say on removing sub-optimal implants, and it's much harder to earn them back. The game is clearly better with free customization of implants. But we had to argue back and forth to get that, which was extremely frustrating.
Today we're still waiting for a blueprints rework. There you acknowledged the problem right away but it's been the way it is since day 1, and changes aren't even in the works. The current way this works is you can still get blueprints for things you've maxed. With an ever expanding pool legendary of things you can get, it's becomes impossible to get a sufficient amount of blueprints for anything legendary without spending cash or a-coins in a lifetime, that's where costs become astronomical. Too much for most free to play you essentially have to pay to upgrade your legendary stuff to max. With legendary gear being designed to be the best, it becomes pay to progress. Not progress faster. Just to progress. That's a very big problem.