So this strategy's end goal is to get two panthers. T1 composition is 3-4 Grens and 1-2 weapon crews, at least 1 MG42. Sniper is also a viable option.
T2 build is minimal, one, maybe two paks if necessary. A Pgren squad if only 3 grens were purchased, or maybe a Pgren squad late game just for schrecks (maybe there was a backtech to SU85?)
The mid game is key here; typically, one gets T3 and a P3 or two and a Tiger. However, it can be viable to go straight for T4 for Panthers if:
The Soviet player is waiting for call-ins only (M4C sherman, T34/85, IS2)
The USF player is waiting for M4A3E8 Shermans
I usually get no more than two Panthers; Pak 40, double Panther and a Schreck Pgren squad should be able to solve your AT needs.
Lightning War and Blitzkrieg Doctrine are my two favorites because of the Stuka Close Air Support. That ability shreds any armor, IS2 or Jackson. It also attacks infantry and serves as area denial. The AoE is huge.
Lightning War and Blitzkrieg both have pros and cons.
Lightning War lets you play to the metagame; you can stall for Tiger if you're getting fucked in the ass. G43s can also be good on certain maps, or for heavy Gren play, allowing one to use G43 squads a bit like Pgrens. Tactical Movement can also be used to rush in infantry squads.
Blitzkrieg helps with armor survive-ability because of Panzer Tactician. The Command P4 is a good supplement to one's forces; it has decent AI and all units take 80% damage.
Getting a P4 in your army composition - Command or T3 P4 - is worth it. A third panther isn't really necessary in 1v1.
Having control of at least 1 Muni point and having several muni caches around lets you spam the fuck out of the Stukas. After the enemy is done repairing and reinforcing, you can call in another run.
In this game:
I stalled for double panther and went Blitzkrieg for a Command P4.
I built three Gren squads, MG42, Mortar, Pgren. I let the Pgren die a lot

I went with the mortar because I thought I could shell the enemy mortar. I'd rather have the enemy mortars firing on mine, not my HMG.
Some criticism:
I built two fuel caches to get to T4 quicker which, in hindsight, really weren't needed because of my harassment of the enemy fuel. I would've been better off with even more muni caches. I left my panther in my base for several minutes, until I saw the first IS2.
Question: Is it worth it for my panther to shoot at infantry squads? Doesn't seem like it would do much, but knocking off a model or two may help me win an important engagement?
I should've laid more teller mines, but I figured that, with IS2s instead of T34/85s, there would be less of a chance of armor attempting to penetrate my lines.
I didn't get a Pak gun until later.
What do you all think about this?
Edit: not making this a jarbled mess