I just finished watching some tier 6 CW battles, with teams using multiple Cromwell Berlin. I can't help but wonder if the match would have had a different outcome if all players had access to extra 5 degrees of gun depression, 10 mm more of side armor, and better terrain resistance. Maybe they would be able to get their gun down on targets with ease and get to position faster, too.
Everyone who has a Bromwell runs it because of the extra gun depression over the regular Cromwell. That's an unfair playing field putting a premium tank that some people paid real money for against those that couldn't afford it or didn't get a chance to buy it. Either balance it or make it available in the tech tree for everyone. WG didn't change the big picture of medium tank balance: a standout tank still exists (Cromwell -> Bromwell), but now only a select group of players have access to it. That's not fair.
The ending picture is more imbalanced than it was before.
And before you tell me tier 10 isn't the same as tier 6.