Geschutz normally has the marder gun, I don't quite know when it was changed back to the ridiculous 185 dps gun. (Though relic nerfed it in one of the later patches so we may have just implemented the relic changes)
That sir is where you are breaking my balls.
Marder deals way more DPS mang. Geschutes is 1 hard hit. Or you pay for higher dps.
Then the marder locks down and deals that DPS for free(and penetration bonuses)
EDIT: Which i forgot to mention!
Terror needs geschutes buffs