No matter what "wunder waffle" the Germans could come up with, they would still fail due to infighting in the upper command structure, poor doctrine and good plans altered by the Fuhrer.
The Battle of France was one of the first failures, as the "pause" at Dunkirk (regardless of who gave the order) allowed the Allies to save a crucial amount of men.
The Battle of Britain was the next failure. The list of "what the Luftwaffe did wrong" is a long one, but to sum it up, the Allies should have awarded Goering a medal for his contribution in defeating the Luftwaffe.
The He100 had potential, yes. But it required Daimler-Benz engines which were in short supply. It had engine cooling issues (even with a conventional radiator) and it was lightly armed.
The Fw187 was a serious contender *IF* left in it's original form: single-seat fighter.
The He112B would have been a solid platform to perform ground attack during the BoB. It's performance was comparable to the Bf109 and like most fighter-bombers, could defend itself, unlike the Ju87. And this would have been before the debut of the Fw190.
Pretty much nailed it, here, Dave. That first sentence explains why things are not going to change much in terms of outcome off the bat.
To add to the Fw 187, again, had it been put into production as a single-seat fighter, which would have been a very impressive fighter, but what wouldn't have been built? Fw 190s, which were arguably more important to the Luftwaffe than the hope the Fw 187 might have been, particularly in that the Fw 190 was a far more adaptable airframe. For the Fw 187 to become anything beyond a single-seat day fighter, in reality it would have had to undergo serious redesign to have become a completely new airframe, contrary to the wishes/hopes of the Wehraboo community.