Well weapon racks are a feature of the US forces which allow to equip any squad with Bazookas, I don't really see what's so problematic about, you gonna retreat squads from time to time so you will have eventually the option to equip them with weapons.
Schrecks are better, but can be only upgraded to volks or panzergrens.
If you think a King Tiger should be easily taken out by a bazooka blob than I'm glad that I don't share the vision of your game, where infantry blobs can take out any super unit.
IS2 & Tiger 1 have equal times, so again I don't see the problem here.
If you buff bazookas to panzerschreck level I guarantee you will see every squad equpped with a m1919 + bazooka. Armour is not needed anymore and your enemy won't produce it anymore. Welcome to a boring new meta.
Relic changed the ability for panzergrens to have only one Panzerschreck for a reason, people were just blobbing panzergrens and annihilating infantry and tanks likewise.
Since you can equip every squad with bazookas, the same will happen.