Just my own personal opinion -
Replace the Dozer blades with the E8 in the USF commander so they can be reworked.
An M3 Lend-Lease supply HT for the UKF also sounds like a pretty interesting idea, it could also drop the M1 81mm mortar to save the slot for something else as well because I don't think the Brits would make that much more use from just a simple HT. Thinking about it now I would really like to see RoastinGhost's 4.2 inch mortar perhaps.
As far as the Wehrmacht goes their abilities seem a bit underwhelming when compared to others, changes to Ass Grens are nice but Breakthrough Equipment and the Panzer IV J seem like worse versions than the German infantry ability and the regular Panzer IV to be honest except that it already comes with the side skirts.
I also made a topic some time ago and people seemed to rather like the idea of an Ost KT instead of the Ace:
https://www.coh2.org/topic/84930/tiger-ace-poll
Some form of repair and forward retreat point for these guys I think would be very nice as they would be the only Army left without a forward retreat point and their repairs are still lacking. A repair halftrack, the infantry upgrade from the German infantry doctrine or the Forward Supply HQ would solve the issue, especially the last one would be 2 birds with 1 stone.
OKW looks solid but I think that there would be a nice spot for a StuG there for some reason, there are even voice lines for use. Make it a little Mechanized sort of doctrine for them.
Again, just my opinion.