Okay, trying again.
If you want the He177 just say, "I want the He177." Trying to prove its historical significance is a waste of time. We can argue the reasons all day long why it failed, but the fact is it failed. An AH 177 would have none of the disastrous historical problems, so what you wind up with is a plane with all the strengths but none of the weaknesses- like many other planes we have.
You must admit though the argument for adding anything German or American at the moment is pretty weak.
On the German side you have the only two jets, one of the finest, high performing piston-engined fighters, one of the most versatile medium bombers of the war, the only tank of the game, a murderous anti-aircraft/assault weapon (with how many actually manufactured and deployed?), and various models of the two frontline fighters. Pity poor Germany.
On the American side you have undoubtedly two of the finest bombers of the war and representatives and variants of 5 frontline fighters, a torpedo bomber, halftrack, LVT's, and carrier task forces.
Italy has two fighters, only one competitive.
Japan has three fighters, bad-medium-good.
Russia has three fighters and two ground attack planes.
Britain has one of the best bombers, a perk fighter, a ground attack plane, and variants of the Spitfire.
It's obvious where need is, now isn't it? Are we still talking "fair?" Talk to the Italians and the Japanese about their planes that could be included, planes that served in large numbers and made a significant contribution to the war. Talk to the Russians about the massive numbers of units produced and deployed.
See, you know all this already. I do think we sometimes get so wrapped up in what we want that we forget how much better we have it than the other guy.