Stukas were cannon fodder during the Battle of Britain, which prompted their relegation to areas where Germany still had air superiority. Even the D or G model, by early war standards, was nothing to get excited about.
Now...a G-model tankbuster with twin 37mm guns under the wings, that's something to think about.
I this old dude's humble opinion, we have all the aircraft we need to achieve a 'balance', meaning that in-game, from a non-historical perspective, we have planes that can do just about everything we need them to do.
So what we're asking for, basically, is eye-candy - aircraft with different configurations that can do what existing AH aircraft can already accomplish.
In looking at the AH lineup, there's only one aircraft in my opinion that can radically alter the state of gameplay as we know it, and that's the B-29. When you look at payload, range, armament, etc., it's the only aircraft not in AH whose attributes are not already covered by existing aircraft.
In gameplay, a Lanc can replace a B-17 which can replace a B-24. A Ju-88 can replace a Ki-67 or a B-25, a N1K1 can replace a P-51 or a 190D-9. Historically accurate? No. Perfect matches? No. But in the end they can all accomplish the same thing.
Everyone is hoping for that wonder-plane that will make them a better play, or make their playing experience more enjoyable. For some, it's a B-29, for others, a Gloster Gladiator or Cr.42 Falco.
Personally, I'd like to see night fighters. Maybe they only become available after certain hours on the arena clock...who knows? But a 110, Ju-88, or He-219 with oblique-firing 20mm would certainly add an element to the game.
Jeff