I think the Ostheer Stuka run's AT ability needs to be buffed a bit because right now it hardly does anything to tanks. This is mainly for 3 reasons.
1) The BK 37 fires merely 37mm shells.
2) The rate of fire of the BK 37 is pretty low
3) The shells doesn't have a "home in" ability in the likes of the PE Henschel run.
While the 1st reason is pretty valid, I think that reason 2 and 3 should be corrected. This will be compensate for the low individual damage of the 37mm. And remember that in real life, pilots are able to adjust their flight path in order to hit their target. In COH, engine limitations prevent this and the best one can do is to make the shells home in.
I think this will make the Stuka run worth its money a bit more.