Osttruppen.
Artillery Officer (boosts panzergrenadiers or grenadiers).
Urban Assault PGrens.
Trench.
Camouflage.
Personally I am not supporting the mate who started the topic.
Few comments about your proposal.
The best defensive unit for Ostheer is MG42.
So, according to that no one of your suggested units may perform an attack
one of the golden rules of war states:
war cannot be won by sitting in defence
Osttruppen - suck - has to be in cover = only for defence.
Artillery Officer (boosts panzer grenadiers vs grenadiers). - suck - Support unit. Comes with some useless commanders. (noone uses Assault Support Doctrine nowadays) He is only good for Panzerwerfer additional barrage for 80 ammo.
Urban Assault Grens. (Does anyone have them? Could some one to prove their effectiveness? well instead of one MP44 PGs have flamethrower)
Trench.- defensive option. magnet for any types of grenades.
Camouflage -sucking expensive defensive options.