I feel like Volks Grenadiers being inferior to Allied Infantry is how it should be. The issue is Allies have plenty of vehicles that are far too powerful at wiping squads. T-70's/Stuarts/Shermans/M8's/Quads are so powerful against infantry that Axis squads don't have much of a chance.
OKW also really need to get the MG34 non Doctrinal. The Teching and forward bases is super gimicky and bad for gameplay, which only promotes blobbing and camping. Removing forward bases in favour of buffing resource penalty would be great. But One shot wipes or light vehicles murdering squads on retreat is a huge problem too, because it means Elite 4 man squads are too risky to use.
The fuel penalty exists for a reason, one of the reasons being the incredibly low teching costs. It's completely unfair to pull out numbers and say Panther costs 235 fuel.
I don't see how hulled in tanks are vulnerable or exposed. It's pretty much instant to cancel them and just immediately drive away, plus it's free to dig in. How is a hulled down tank any more fragile than just a normal stationary tank?