Profile of kamk

Keep in mind that OKW has a 66% fuel gain, meaning you gain 50% more per minute, also meaning any loss a fuel based unit hurts even more for OKW.
Their design / advantage here is the rather cost effective teching with goodies - in case of T3 it's obv. an HQ with a fancy flak gun on top, while losing it will also mean a complete (!) loss of teching and buildable units.

A forward position has several weakspots:
- AT guns and vehicles can attack ground at max range, they do not need vision for this, so Zis & SU76 are quite good there
- you can also smoke the HQ, and then attack it
- off & on map arty helps a lot on speeding up the process, or just killing it by itself
(current meta vs. OKW often involves ML20s)
- SU85 can self spot and securely attack it
- mortars outrange it by far, but you should of course prepare yourself for a counter attack
(you also force him to send his 320mp Pios to repair it, which often bleed while doing so)

Overall the effort is rather small, and you should never try to overcommit your army by pushing against fortified positions if you can't achieve anything. So just take everything else on the map, and box him in.

Defensive stance can be near immediatly cancelled now, so crushing is a no go.

That is correct. But you will keep him from using it, and you can still crush "the normal way", not?

The other options have already been mentioned.

Post a replay please.
Otherwise see my cliffnotes.

I can assure you, no wins or losses of yours were due balancing issues.

So just enjoy the game.

Trust me. P.Grens wreck Shock Troops in pure 1 on 1.

Shocks own any other infantry on close range.
If you a-move through negative cover and lose already half their health on the way, that's another story.