If you're not, use attack ground with howitzer mounted tanks. 105 sherman, KV-2, ISU-152. They're all a lot better with attack ground. KV-2 has more HP and armor than the brummbar, but its projectile is slower. It also deals decent damage vs tanks because of deflection damage.
I think aura heals are pretty dumb outside base sector. Especially Brit ones which are super spammable. I’d rather see a cost reduction on the gren kits. You don’t ever use them unless you have 4+ models anyways.
Replays help if you want direct tips for feedback on your play.
If you can handle light vehicles I suggest them. If not, either 2x LeIG or stuka zu fuss to handle team weapons.
Blob your volks. Volks are awful in 1v1 situations.
I don't recommend grand offensive anymore. Tiger is meh and something like breakthrough is probably better. Spec ops is always nice because flares and if you like firestorm I suggest keeping it. It's niche but it can be pretty great in the right conditions. Fortifications is also nice, but imo it doesn't really bring what OKW needs. With it you're lacking a lategame callin and relying on LeFH spam and maybe a 43, both of which get countered by offmaps of which in 99% of all games someone on allies will have them.