As the title says, I suggest that the passive effect of this plane should be tweaked to make it better, technically is the only "guard" for germany to use but the damage it can does when a ground unit attacks the HQ is so little it not that great.
So I suggest 3 ideas:
1- the most simple is to rise its damage from 1 to 2, so there is more pressure and punishment for passive damage related units.
2- changing the "ground unit" to all enemy units so that even planes can even trigger the 1 dmg effect. (hidden condition: it won't trigger if its the same effect from an enemy heinkel he 219)
3- same as the 2nd option but with a little more damage.
I'm aware of some friendly ground units (japanese and soviets) that can damage your HQ and trigger the effect if we follow the vanilla effect and 1st option, I've tried it and is so inconsistent to try it, that is not worth the effort to build a deck around that effect.

