Played a couple of games with ze Germans, here's my opinions:
221/223 is very, very nice, however it would be better I think if the Logistik upgrade would be separate since it makes sense to limit the FuG to 1 because of the vehicle sensor but not for the lockdown ability.
Maybe the FuG could be separated into 2 upgrades:
Command Car and Logistiks Car, the Command Car being limited to one and having the Relay and the Logistiks Car being able to capture and lockdown territory? Sounds fair to me, at least on paper.
The 250 for German Infantry came at a surprise for me but I still think it would be nice if it could reinforce as well, I would go as far as to be willing to pay for the ability even if I'm honest. Reinforcement upgrade for like, 40 ammo or like, some manpower and fuel, similar to the 223 FuG upgrade sounds good.
Stormtroopers are still... well I wouldn't go this doctrine for them that's for sure.
It looks to me like the 5 man squads is probably going to be the 1 and only reason to go this commander sadly in it's current state, I again propose the F1 Panzer IV with the short barrel be added instead of the Sprint ability, something new and unique to support your infantry, as it was it's intended role in real life as well, that's the reason for it's short barrel 75mm gun with the intent to "bust bunkers" so to speak, the Panzer III M with the long barreled 50mm gun was used for AT purposes but lacked good HE ammo, hence the use for the Stubby PZ4, just some background info.
As for Defensive, the Bunkers are a really nice blast from the past, as is the 223 for the OKW, however sadly they overlap with the regular bunkers too much and are in the same case as the MG42 was for the OKW Fortifications doctrine, it's nice, it's superior to what you have by default but there is too big of an overlap, plus as we can all see they might present a balance problem.
The repair pioneers are a really big welcomed addition to a basically repair-starved Army so to speak.
So with the idea in mind to keep them but also do something with the Concrete bunkers I thought of these:
Additional bunker upgrades could be combined with Defensive Tools instead of the Pak 43.
Concrete bunkers either replace or are an upgrade for regular bunkers, similar to the UKF Fortified upgrade for emplacements for the Advanced Emplacements Regiment, to get rid of the overlap.
I even thought about combining the Pak 43 with the Lefh 19 but then again that would leave a black hole in a fair bit of doctrines with a new freed up slot.
So then I thought about having the LeFH 19 replace Sector Artillery, and have the Command bunker get it instead, or Bunkers get a "radio" upgrade that allows them to setup a forward retreat point and call in sector artillery, similar to the Defensive doctrine for the Wehrmacht in CoH, difference is that they could only call in registered artillery on themselves.
I think that given a Command Panzer IV instead of the StuG E, a LefH 19 instead of Sector Artillery, and Sector Artillery instead being given to either the CPZ4 or the Bunkers through the Defensive Tools, as well as a Forward Retreat point, would give the Doctrine enough support utility to warrant bigger use from players.
Sure you won't have Elite infantry or Tigers, but heavy guns, a forward retreat point, repair pioneers, a Commander in a tank and loyal non-German soldiers to build and man your lines would surely be enough to hold the line against the Xeno... erhm I mean Soviet dogs.
Edit: Of course alternatively the Pak 43 could still be combined with some Bunker upgrades instead of Entrenching Tools to give the commander slot some more utility, or maybe an upgrade for a 17 pounder style emplacement around it for some beefed up protection so it doesn't get insta-nuked?