I don't understand this "midgame weakness" of OKW, they have P2 and Puma which are excellent vehicles and also rocket arty in the same building which is good vs teamweapons like maxim. STGs being relatively cheap upgrade with good moving DPS and good midrange damage also gives OKW a boost in the midgame. ...or are we talking about early lategame here? Can you specify the mode and timeframe?
Puma is not the old Puma and will only be used to counter LVs yet Stuart can fight it effectively with the blinding shot.
P2 is mehish compared to T-70, AEC and Stuart which all counter it.
Rocket arty is absurd in teamgames with blobs but a suicide in 1v1 (to rush it I mean)
Any mistake against OKW and you are screwed too. This works both ways. They can turn your teamweapons into their fuel in seconds if you mess up or get flanked by Sturms. Game punishes bad plays and rewards good ones, just as it should be.
Bleeding them and forcing them to go home is quite easy tho. Sturms are thrash in maps like steppes, crossing etc. I agree they perform superb in cqc maps like bilasytok (???) market but on open maps they are just meat for rifles and IS.