The powerfulness of Shreck isn't the shreck itself or volks, just that OKW can spend all its ammo in it.
What make 1919 good but not that overpowered, the fact USF need ammo for many others abilities. Of course you can decide to invest all your ammo in it, but at the end, that's a strategic decision and it weaken you somewhere else.
Make volks shreck blob costing the same, but add or increase all other ammo prices of OKW abilites, add an ammo price to obers LMG, to falls, to jaigen
to panzerfusiliers etc... and you' ll see a decrease of shreck spam. People will have to make strategic decisions again and decide how best invest ammo and fuel to have enough AI and AT on the field.
Today it is just easy to spend any single munitions point on shreck since you know you'll have ammo free AI stuff.
Jaigen?
I think you meant Jager. Is it even worth paying for their G43 that snipes people if it's implemented. I don't see many people use it very effectively.