What suppression tools does the OKW have?
Early game: Kubel. This guy requires a lot of care, and will likely die to schrecks anyway, but early on he can put you in a good position.
Mid game: Flak halftrack. This thing when used properly is a complete beast. This is honestly one of the strongest counters to infantry blobs as long as you keep him repaired and be ready to screen an escape with some smoke.
Late game blobs you really need artillery to contend with, which is fine because OKW has it in spades.