If my understanding of the unit is correct, to remove pfausts from FSJ is a bad move, because:
OKM infantry is analog to OST armor, overall good and costly enough, not really cost efficient, but effective.But the downside of such generalist design is enemy variety, because cheaper and/or specialized units can and will harass a stronger axis units in specific scenarios other than plain combat (cost efficiency, versatility, scaling) and usually axis units have a finite powerspike, faster games favour allied, stalled games favour axis, generally speaking.
FSJ is as it is now (it can be changed though) is an elite doctrinal mainline infantry, projected from the volks design and not an elite AI specialist, therefore the presence of pfausts. Volks after upgrade are effective at all ranges, so are FSJ, volks have snare to be used as a part of a combined assault, so are FSJ, both have grenades but FSJ have better abilities because of their higher price (compared to volks or obers) and have camo because their original role was ambush (it is a bit redundant now TBH)
Instead of loosing pfaust, remove camo, but instead of removing camo or pfausts IMO FSJ should get an explosive satchel or the bundled grenade to stun vehicles, simply that.
If FSL are "mainline" infantry they should builded from base sector, not deployed in any point of map. Also, they could get the same ability like guards have - "soft snare". Explosive AT satchel like penals have, too OP due camo.