Aside from gameplay additions, I'd really wish they would revisit Tank Destroyers.
They are supposed to have guns equal to a tier higher or better and able to engage targets in front with superior firepower. But as it stands same tier heavies, and mediums in some cases, have equal firepower to the TD's only with more HP, agility, and a rotating turret.
The only tier TD's that feel like they are finally true TD's is tier 8, where their gun is upgraded to tier 10 guns and actually is stronger than equivalent tier 8 tanks.
There should be some trade offs for playing a tank without a turret. Having lower HP should not be that trade off.
(Yes, American TD's have turrets until tier 7, and TD's have better camo values but because of WG, it's hard to determine what is good camo vs bad camo on TD's)