This is a quick riff raff for ostheer
There are three doctrines represented by 3 familiar generals
1 Walter Model
The defensive option. Works more as elastic defense.
I.E think PE but have some static defence capabilities like faster built and cheaper bunkers.
It is a defensive doctrine but is to counterattack while static stuff hold the line for a short while.
Emphasize on quick units like troops carriers and light vehicles.
2. Erich von Manstein
Overall infantry and tank doctrine with various general buffs and stuff, however has the most powerful artillery and the doctrine is well suited to assault fortresses and static defenses.
Emphasize: good all around with best artillery
3. General Guderian
Tank oriented
Gain access to the (BLEH BLOAH was out of ideas but don't want tiger or king tiger) elephant (1 of the 2 that was on the eastern front)
Overall tank assault buffs.
Veterancy system
As the ostfront soldiers already were veterans infantry and tank get instead new equipment as they level up.
Example (riff raff should be seen as standholder)
1. Grenade or medkit
2. Shrek or lmg
3. Assault or cloak
Tank (even more riff raffy)
1. Scopes or improved tracks
2. improved armor or improved health
3. Improved anti tank gun or improved anti infantry gun.