Ok now my explanation as I 99% axis player (not yet a fanboy

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Volksgrenadiers are very lackluster and die quickly for core infantry.. Sturmpioneers lost a lot of their capability when they basically got a range nerf. Fallschirmjaeger are just waaay too flimsy for the price you pay for a 4-man squad that clumps
Volksgrenadiers are without cover the weakest inf early game that's true, but they are the best in late because they scale so well. I don't know the exact stats but they get IIRC two times a modifier which makes them harder to hit. Fallschirmjäger are still very strong if you hold them on long range. They are not meant to be German shock troops, they are better grens that can clear out support weapons from behind. When I play as allies I have a lot of problems against them.
On higher vet ranks they are basically like Obersoldaten.
If Volksgrenadiers are to be a "meat shield" to draw attention for superior closer range squads, they need to be more durable.
As I said before you have to care of them in the early game while they become surviving experts with vet.
Volksgrens die quickly with or without vet, priests, ISU-152's Shocks, Rifles etc instagibbing them as soon as they come into view doesn't help.
ISU was bullshit OP so it got a very huge nerf. Priests, ISU and Shocks are all commander based abilities which means that other units won't hit the field.
Jaeger Lights are okay, but the doctrine they are part of kind of sucks, Ostwind is expensive and only good for a short time, comes in way too late. Everything on the Special Forces doctrine comes in way too late. LeIG for OKW sucks, right out.
Haven't played Jäger post patch but the Ostwind is one of my favourite tanks of the game. Especially against rifle blobs you do tons of damage. And it still is good in the late game you just don't have to put it in the first row. The LeIG is IMO a thing about luck. I had games where it didn't hit anything and I had games where it had 40-50 kills in the end.
The entire Elite Armored doctrine sucks, and the Panzer IV Ausf. J's are never worth getting, despite that they come obscenely late to make a difference.
While I agree that the P4 J are some kind of weak I have to say that the armor pen ammunition is quite cool because you will penetrate most of the time even with pumas.
German MG's cannot suppress anything it seems and often don't fire until Allied units make it halfway through the long part of their firing arc!
Even an MG has to be supported. A lonely MG will maybe surpress an enemy squad but others will flank it and kill it. 2 MGs are doing amazing if you now where the enemy is going to attack you.