Lets not kid our selves an AT strafe 1 shotting 2 IS2's or 3 shermans is the same as 2 Scotts or other light vehicles literally kissing each other.
What needs to be toned done in CAS is the retardly efficient "use at your pleasure" conversion and the AT strafe doing 80 deflection damage.
The AT strafe killing even 1 medium in one fell swoop is stupid. The AT strafe deals 120 damage on pen and 80 on deflection. A medium is a minimum 100 fu investment, and since USF and SOV have no choice but to build these stock (unlike OKW and OST who have panther), no offmap should be capable of killing them outright. Hell, the supposedly OP P47 can't kill a full health medium in even 2 strafes.
The AT strafe needs to be nerfed so it can keep its heavy AT damage, but not murder mediums completely. Shifting it to a flat 80 dmg on pen/bounce, would keep it effective vs. ISU and IS2, while at the same time making it impossible to fully kill a medium in one strike. (not sure how many rounds it fires, maybe need more tweaks)
There is no reason that old squad-wipe IL2 was OP while current vehicle-wipe Stuka AT is not.
In terms of the conversion, I agree. No instant-conversion ability should be 100% efficient. It lets players make choices and get the best of both worlds (early lategame infantry which can snowball into faster armor thanks to map control). Conversion should either be less efficient, be similar to luftwaffe supply (but that would make luft supply useless), or always be on in the style of Soviet Industry.