I think everyone realizes there are lot of underperforming/overperforming tanks.
I think WG should focus on balancing these before introducing new tanks... I'm not saying to nerf or buff into oblivion.
Just a few examples of underperforming would be: Panther 1 line, Tiger 2, Caernvaron Foch 155
and then the overperforming T67, Cromwell, T29, M53/M55, Swedish TDs, Defender, 0-1 Exp, Hetzer, etc.
There are a lot more and maybe people will have a different of opinion on which tanks are too strong/weak but data can be obtained which doesnt lie.