I'm now imagining the horrible things the Finns would have done to the Red Air Force if a ASB had given them a radar network and 250 P-47-Ds and the parts and training to maintain them
Finland was exactly why I was trying to puzzle out any effects of divergences in the east of course. Assuming the Norwegians and Allies drive the Germans out of Norway (and Hitler seems unlikely to countenance any retreats, so that means killing or capturing all the invaders present and any more Hitler might manage to send in after them--the best the Reich forces could hope for would be Hitler at least having the sense to cut his losses and stop sending good after bad) then a major divergence going forward is the Allies having secure contact, albeit tenuous, directly with northern Finland. Note the Soviets have no border with Norway; that was achieved OTL later in the war with the Soviets seizing Petsamo.
The ugly fact is that OTL the Finns were co-belligerent with the Axis once Barbarossa was launched and got major aid from the Germans. It sure would be nice to avoid that, and in fact to avoid any further war between Finland and the USSR, so I was rather wistfully hoping that the prospect of Allied aid going direct to Finland might deter Stalin from the mistake of further designs on Finland.
A difference the (quite hard to explain or justify, and in that sense fortunately not a factor here, sad as the whole ugly story of the German-Soviet Pact was OTL and here) lack of a Pact might make would have been defusing Allied animosity against the Soviets.
If Finland can be secured without further fighting, that seems good to me.
Obviously the level of Finland Wank you are imagining here is a bit premature to say the least. It is not crazy something like that might happen later, because at this point the Soviets are indeed complicit as hell in the Axis's war, and a DOW against the Soviets is possible. Ill advised unless Stalin does something egregious of course; it was wise OTL for the Allies not to burn the bridge of later Soviet alliance, but the ball is in Stalin's court at this point.
(I don't think Stalin is likely to put his head further in the noose though, nor will he actually attack the Reich himself out of east Poland, though certainly on paper it looked like he planned to do just that sooner or later. I think he was going to procrastinate on that as long as Hitler let him, because actually what was deterring him from attempting some kind of Bolshevik crusade was his own fear of empowering some successful Red Army general to rival himself).
For Hitler to be able to eventually strike east at the Soviets, I figure he has to conquer France first.
Of course he himself is perhaps crazy enough to order it anyway, and I would not count on the German officers being able to pull the plug on his lunacy by couping him out--they tried it more than once OTL and it backfired on them, and aside from having the Devil's luck, which could be a rug an author might pull out from under him, institutionally speaking there is no "clean" way for an officer coup to be pulled off without weakening the Reich with civil war; the Nazi machine was pretty deeply wound and too many Germans would follow it; even killing Hitler is no guarantee of a quick orderly shift of power. To be sure if Hitler tries to arrange Barbarossa without having settled the western front and capturing western European resources first, the officers might be driven to try anyway and perhaps succeed enough to win a "white peace."
But the Allies pretty much have to demand the release of Poland and Denmark as a minimum condition, and will want lots of others and would perhaps rather fight for total defeat of Germany than agree to too easy a peace for even an ostensibly post-Nazi Reich to be let off on. Unhanding Czechia is another term the Allies should insist on, and punitive concessions to Poland, reparations to Poland, Norway, Denmark and the Entente powers too.
Can Hitler in fact still conquer the lowland nations and France?
It isn't even settled that the Germans will be driven out of Norway yet of course--but if they are not, that will be a bleeding front, and I think that would put paid to any plans to take France more effectively than Hitler cutting his losses in the north would. OTL, Norway absorbed and immobilized a lot of occupation troops; it paid off for the Reich various ways, but actually without that albatross on the Wehrmacht's neck maybe, writing off what was sent north as lost, they might come out ahead in terms of troops and kit for invading western Europe.
Then there is the whole question of how probable German success achieved OTL in France actually was, with things as OTL. At best taking the Norway venture as failed and pulling in their horns there can perhaps leave the Germans not much worse off for that mission, but set against that the effect on morale on both sides that defeat in Norway would mean--French, Belgian and Dutch defenders would have less reason for defeatism looking at Norway's example; I suppose the Reich can manage news and rumor well enough to minimize blows to their own morale, but at the top Hitler looks a lot less brilliant--even if German troops hang on in parts of Norway, it is a mess for them versus OTL, and that would be a fatal bleeding of resources needed for the southwest campaigns. Meanwhile people debate how likely French defeat actually was even OTL; persons holding that Hitler just plain got lucky there naturally will have to figure that his prospects are grim indeed now! Time was though I gathered most people assumed France's fall was quite certain, and people believing that can probably argue the Wehrmacht and Luftwaffe can be seriously worse off than OTL and still pull it off anyway.
The author alone can rule on whether outcomes in western Europe to the south are as OTL in the end, which I think is anyway not categorically impossible as yet, depending on how much more the Wehrmacht and Luftwaffe will bleed further trying to salvage the Norway mess. Best case for Hitler--he comes to his senses and offers a truce for all Germans to withdraw home minus their kit through Sweden back to the Reich, which the Allies might consider taking to avoid their own losses in Norway. But that's out of character for him, unlikely for the Allies to agree to, tricky to manage and it is not entirely clear to me the Swedes would play along either.
Meanwhile not only French defeatism, but Belgian and Dutch, is on the back foot; the two northern coastal states are of course warned (but they were OTL of course).
What are the chances that Hitler, observing losses from the Norway gamble, decides to forgo invading the Netherlands and Belgium, and concentrate on a hard push through French defenses straight into France without drawing the low country kingdoms into the war at all? I think if he leaves them alone, they won't be persuaded to jump in on the Allied side even if Germany is on the ropes later, and so France might fall without Hitler securing the lowlands maybe, though I do understand that pushing through the Maginot Line will not be easy.
If he can secure just France, and the low country kingdoms remain neutral, that might be enough for him to try Barbarossa anyway, not earlier than OTL of course--the Axis will need time to assimilate French resources and build up the levels Hitler figures are enough and meanwhile Italy will be jumping in and diverting resources and attention to the Med and North Africa.
Can we have another divergence in which Mussolini sits out the fall of France, leaving the whole job just to the Germans? But that leaves Britain stronger, and Norway as a major allied foothold, as noted capable of diverting equipment and troops into Finland and perhaps thus stabilizing the Finnish-Soviet border allowing Stalin to concentrate resistance to the invasion, while Hitler would have less to work with even as demands for more, even in his overoptimistic estimate, pile up. Finland being secured by being part of the same alliance that the Soviets are in gives Britain a land route to link up British expeditionary forces direct with Soviet ones in the northeast; Stalin might even agree, as a condition of British aid, to let the Baltics go and maybe even eastern Poland, though I am pretty sure he would demand at least these buffer states be demilitarized.
See, if it is all the same to you, I'd rather imagine much enhanced Finnish forces beating Axis rather than Soviet forces. I would not forecast that as high probability outcome here, but I can dream as well as you can.
The high probability outcome is that Hitler is dead in the water but just doesn't know it yet, that France will not fall, that the lowland kingdoms might well do far better--surely the Reich can do them heavy damage, but both had plans for turning their eastern reaches into defenses and their populations taking refuge in the west, which would deny those ports as well as French to the U-boat campaign. Even if France loses a lot of ground, even if Paris falls, a stalemate with French forces holding part of France is fatal to Hitler's dreams, and his negotiating a truce is just plain out of character for him.
Looking forward to the author's judgement on how far toward expelling Reich power from Norway the Allies can go. Norway is hardly secure yet! But time is not on the German side.