While a nondoctrinal mg would help, I would rather see volksgrenadiers reworked. Make them cost 300 mp and more popcap, with better stock rifles (grenadier stats?). After 1 truck is built, they can upgrade to either 1 panzershreck and the ability to build sandbags, or 3 STGs and some kind of utility ability (smoke?).
This way, blobbing volks becomes less of an issue, due to their high cost. It will also lessen OKWs propensity to float.
In return, OKW finally gets a good scaling basic infantry force, which can be useful on the assault with STGs, or on the defensive with their rifles and sandbags. It will also make OKW feel more like the specialist army that it was originally, and make OKW more decision based as to where they want their munitions going, making them feel more 'starved'.
Thats just my view on the matter though.
What about obers then? Why would you get obers if more volks would be better? The moment Volks get AI upgrades, is the moment where obers get obsolete.