I recommend Panzerbusche at rifles.
They are already in the game so Relic doesn't have to do any extra work besides moving some numbers around to make them work like the other at rifles.
These would be a mostly defensive weapon for early game to survive the light vehicle pushes. Late game they can already rely on their Raketen, Puma, Jagdpanzer, and panther for strong AT presence.
Whatever they do I would not like to see a snare on Volks, it makes them too much like every other infantry squad.
