The allied TD's are not lacking in penetration (40 and 20 less) and the slightly better damage is around 25% for the jackson (and lol at the jacksons vet 1 ability) and 50 % for the su85. whatever they lack in penetration they make up more then enough with much higher dps and being cheaper. and in the okw case being much cheaper. you can easily field 2 jacksons/su85 for each panther.
So saying that the allies lack heavy AT is wrong. In fact its the other way around.
I never said allies are lacking in heavy AT, I just said that 375 armor value isn't equal for allies and axis, for example there is not a single allied unit with 350+ penetration while there are multiple axis ones. Also you are confusing DPS with Rate of Fire. DPS is a result of damage+rate of fire+penetration put against certain armor value and varies if the armor is greater then penetration depending on the armor.
Jackosn vet1 is bugged, at least the damage part, otherwise its one of the best TD abilities around.
Also please don't go certain other individuals way and don't compare units in vacuum, you'll never have just 2 SUs against panther, there will always be additional factors of all other units around. A pair of SU-85 isn't equally lethal to armor as 1 panther and 5 shreckvolks.
Do you play 1vs1? let me tell you the okw struggles against the is2 simply because they lack the necessary damage to deal with the is2. this is part because of the callin meta but also because their are no fuel caches.
Not enough to call myself a 1v1 player, but enough to understand what is going on there.
OKW problems against IS-2 do not originate from the IS-2 stats or OKW AT, but from the fact that they will inevitably fight a pair of them, just like allies will inevitably be forced to fight 2 tigers.
Biggest balance issue with heavy and super heavy armor is and always was the fact that they are not hard capped to one at a time, which is a direct cause of call-in meta and skipping tiers by sov and ost.