The 222 should perform like a scout car, because it is a scout car.
This. The 222 should be able to protect isolated points from lone capping units, harass enemy snipers, and provide good reconnaissance to enhance the effectiveness of MGs and AT guns. It shouldn't be a counter to light tanks, Ostheer has enough of those already. It shouldn't be an offensive shock unit, that doesn't fit with the faction playstyle or the other units available at that point in the game.
With that in mind the 222 could use a slight buff to its firepower against individual infantry squads (with a commensurate cost increase), and some other improvement that enables it to kill isolated/fleeing snipers more easily. Vet bonuses should work to enhance its reconnaissance capabilities so it can remain useful later in the game. It doesn't need any buff to its penetration or survivability.