Reduce plane damage. Yes please.
Soviets
ISU HE nerf? No. ISU's main role is AI with some AT capabilities. The AT on the ISU is decent but not great. It doesn't need a nerf to its primary role. Rear armour nerf is unnecessary too. High HP panthers with high frontal armour do not need an easier time killing an ISU.
Recon removed is not necessary. Get AA. Or better yet, use the Schwer AA since it comes with all Schwer's.
Healing would be nice to match the HT on Wehr side. Cost adjustment may be needed though.
Wehrmacht
Spotting scope elefant is what makes it strong but it immediately goes away when it moves anyway. Having that first shot capability (without infantry) is a major strength of the elefant and I don't think it should be removed.
Yes to the stuka dive bomb not neutralizing victory points. Its just stupid to have a super close game and then have 2 players coordinate their stuka dive bomb.
UKF
Love the mortar pit idea. Reduce build time of mortar pit slightly to adjust for having to upgrade to 2 mortars? Stay away from my Infantry Sections.
Land Matress definitely needs some work. No tear down time would help it from being stuka dive bombed constantly. It should be non-doctrinal too since brits have no way to counter blobs (similar to how you mention OKW later).
Never had the issue with the red flare. I wouldn't mind all infantry section members throwing red flares but then how do you know which flare the barrage is targeted?
Perimeter Overwatch adjustment. I think this is fine as it currently is, its expensive, its strong, but there are only 2 guns at the base and some off map mortar so there is only so much it can do. Plus it can be countered by love tapping a point with infantry which is very easy to do.
Assault Commando. You say obvious reasons but I don't see the obvious reason? I rarely see this used in team games.
OKW
Funny how you say OKW needs an important tool against blobbing when Brits don't have any. I do agree on the rework though. Stuka is a terrible unit with terrible design. Not quite sure if turning it into a random scatter mortar or incendiary barrage unit is the right choice. Damage over time is not as effective as immediate damage. I can offer no alternatives either. Maybe increase the spread/scatter on the bombs coming down instead of being insanely accurate in a row (like a creeping barrage unlocked at vet 0). Perhaps limit the current stuka to 1 so while it stays powerful, they can't mass the unit.
G43 agreed on this change, its more of an exploit.
IR HT. I don't think pop should be lowered, its already pretty powerful offering free vision in exchange for a small investment. It combos well with other Axis units too.
One minor change I would like to see is making a repair unit more accessible to OKW without the 300MP cost then again thats what the Mechanized truck upgrade is there for. Perhaps through a new commander or something.
Oh and remove the cap on King Tiger. Let me have two King Tigers

USF
Pack Howie doesn't need a change. Its competiting with IG and I'm pretty sure they both share similar stats. Pack Howie is one of the best blob controlling tools USF has and its unreliable at that. Excluding mortor carriage and MG.
M8 comes too late as it is. Reduce CP cost if you are going to nerf damage or keep as is due to the high CP cost.
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I think the biggest issue is Brits lack a blob control tool for team games.