What if I don't pick Guards mortar? You expect Allies to stop Panthers, KTs and Jagds with 1 IS2s and bunch of garbage mediums?
Use soviet TD's and ZiS not T-34/76's, backed up by mark target you can counter heavies fine. JT can be pushed back by a single AT gun and once flanked/caught out of position is hopeless thanks to stun locks.
KT is so slow you can counter it with any vehicle over 40 range.
Honestly OKW players that know how to use Jagdpanzers and Stukas are far more scary than someone holding out for KT spam.