It may well be the case that assault HQs, at least for Soviets in 1941, are too good.
However, I hope that one thing that doesn't get lost in this conversation is that historically, the Soviets counterattacked in 1941. Not just a little bit, but a LOT. So if there is supposed to be a historical sort of experience in WITE2, then Soviets should counterattack in WITE2.
Now, here's the rub. As far as I can see, with how things are set up, for the most part you only want to attack (in particular with Soviets in 1941) if you have a lot of units to attack with in a battle which have full CPP, or at least fairly high CPP. And with how the game is set up, that will happen a lot more with assault HQs than otherwise. So the problem I see, at least potentially, is that if you take away assault HQs, then will Soviets still have an incentive and ability to counterattack?
Another consideration is it seems to me like there is often a pretty massive difference between the manpower/equipment lost between a successful attack and a failed attack. If Soviets do a failed attack, it can cost thousands of men and way disproportional losses. Whereas if they do a successful attack with overwhelming numbers, pretty often Soviets can inflict almost as many casualties on Germany as the amount of casualties that Soviets take. And because that difference is so large, if you are playing the Soviets and you want to counterattack, you are strongly incentivized to only do high odds counter-attacks which are likely to succeed. And what is one of the main things that makes counter-attacks have high odds and be more likely to succeed? You guessed it, high CPP from assault HQs. So if there are no assault HQs, a side effect of that might be that Soviets simply do not counterattack, or at least end up doing so a lot less often. Even with assault HQs as they are now, I would guess that currently most Soviet players counterattack less than Soviets counterattacked historically, because Soviet players generally are trying hard to carefully pick their battles and only attack if they have very good odds of a tactical victory. That may also be part of the reason why often Soviets seem to take lower than historical casualties - because Soviet players do fewer of these failed counterattacks, and so they don't take historical failed counterattack losses.
If I am on the right track here, then it might help if the incentive to counterattack (attack) were a bit less tied to whether an attack were actually successful. Historically Soviets launched many attacks, most of which were definitely unsuccessful... But they kept attacking anyway... For the player to be incentivized to do lots of unsuccessful attacks, I think there would need to be more benefit to doing failed attacks. For there to be more of an incentive to do that, it seems like the battle results of a successful attack vs. a failed attack should not be so totally different. Maybe the losses in combat results ought to be less binary, with fewer battles where Soviets and Germany both loses about the same amount of equipment (successful Soviet attacks) and fewer battles where Soviets take vastly disproportionate losses (failed Soviet attacks) and more losses that fall somewhere in between.
Another problem is it seems like most Soviet players try to do almost all of their counterattacks against Panzer divisions. There is a lot less incentive to counterattack against Infantry. Which is not exactly historical. Although a lot of Soviet counterattacks were against Panzer divisions, they also attacked plenty of German infantry as well.
So if assault HQs do get nerfed, I just hope that the game designers are careful to make sure that Soviets are still able and incentivized to do counterattacks.