let's just say, right after Anschluss Hitler decided to fetch kaiser back from Doorn, recrowned him as the puppet emperor, like the way he manipulated the senile Hindenburg; and adopted a rather moderate policy on foreign and domestic matters to both appease the royalist element and the British, while giving nazi regime more legitimacy.

So, Germany still split Poland in 39 with now the bigger evil Soviet; UK, France dw on G; Churchill didn't quite make it PM; G defeats France in 1940, French signs Neutrality act and UK agrees armistice.

Summer 41, with relatively peaceful WF, no restrictions on war material import, no commitment on sub warfare and Afrika, Luftwaffe in full strength, Hitler launches Opt Barb, what's the odd now?

any thoughts?

This scenario is so stacked in favor of Germany. Nuff said.

okay, to answer your question, in this scenario there's no Holocaust, no mass deportation, but to not contradict Hitler's previous stand too much, Nazi regime still blames Jews for the defeat of ww1 and the subsequent economic collapse; so they imposed a 'restoration tax' on all Jews(unfair, but not unbearably demanding); Jews(and other 'inferior' people) are tolerated, with full citizen rights, though intermarriage and higher social position are not encouraged, but still accepted. Therefore the regime does retain most Jewish population, but the Jews would be by no means 'patriotic' under such circumstances...

let's just say, at this point, Stain realized that Germany has no enemy left in the west, he might very well take his spy ring's warning seriously and get prepared. What if the 3 million red army were able to retreat in a rather orderly fashion to dnieper river line(giving some 1 million rear guard get wasted covering retreat); set up a rather solid defensive parameter while waiting for mass mobilization to complete, with a benign japan, Russia still able to transfer that 5o divisions from far east...
now, with the red army strength relatively intact plus the massive manpower reserve, how would eastern front play out?

Now that's a little better, Lebowski.
If Stalin had been given the time to consolidate his forces and industry before Barbarossa began, Germany would be in for a very rough time.
Still, Germany has the advantage of having better led units at the beginning because at around this time, the Soviet Army was still suffering from the results of a heavy purge of their officer corps.
I'd say this would bog down to a massive war of attrition between Germany and the Soviet Union.
To put things metaphorically, this could be a fight between a slugger and a boxer. The USSR would be the slugger while Germany is the boxer. In this long term bout, the boxer would have the initial advantage but as the fight goes longer, the slugger will have the upper hand because of his better endurance and stamina. The boxer might score knock downs in the early rounds but the slugger's built to take punishment and would be able to stand up for the next round.
The only way for the boxer to defeat the slugger is to score a knock out. However, with the heavy built of the slugger who's trained to go toe-to-toe, that's a big if.

the West would likely to see both power disintegrate, so if the slugger were to beat up the boxer or vice versa, I don't think UK/France would just set there, would be interesting to see what's American/Japan's reaction in this conflict.
BTW, without sticking to Nazi racial dogma, the Wehrmacht would likely absorb significant manpower from Soviet buffer states and Ukraine, and partisan activities would be kept at minimal as well, that's a factor to consider as well...

Just an observation of my own. There weren't even a million Jews in all of Germany, let alone enough young males in the population to provide an extra few million soldiers. In 1933, when Hitler took power, there were around 535,000 Jews in all of Germany.
(source: Jewish Population of Europe in 1933) The Jewish population could never have contributed to the German military situation numerically. Financially and scientifically, yes, but numerically they were a small minority.

This "what if" scenario is entitled "What if Nazism shifted into a more moderate tone and disregard [sic] racial purity" but then goes on to ask what would happen if Germany had a free hand against the Soviet Union by the Allies making peace with Germany after Germany had made all of its historical conquests in Western Europe. The unspoken link between the title and this second "what if" seems to be the idea that the Allies would not have opposed Germany if the Nazis hadn't oppressed the Jews so badly. This idea, I think, is badly mistaken. While the Nazi treatment of the Jews was used for propaganda purposes to paint the Germans as bad guys, it was never a reason for the Allies going to war. Britain and France supported Poland against Germany not because Germany was mistreating its minorities (Poland was as well, as were most nationalistic, "ethnic" states at the time) but because Germany was gobbling up countries and becoming a strategic threat. If Hitler did betray his innermost convictions (remember that in his final will and testament he railed against the Jews and called for a continuing crusade against them - Hitler's hatred of Jews was visceral and it is simply inconceivable that he would ever backtrack on evicting the Jews one way or another from Germany for good) the Allies wouldn't have cared a whit, I don't think. Their opposition to Germany was geopolitical and strategic and a massive Germany, controlling all of Western Europe, could never be tolerated by Britain. Getting beyond that impossibility for this scenario, I think if Germany did attack the Soviet Union the British would be forced to support the Russians and attack Germany again, even at the expense of losing their entire invasion force, because a Germany controlling Russia as well as all of Europe would be a monster that Britain would have no hope of ever conquering or matching in terms of power. It would be the end of Britain as a world power and as we know, Churchill was willing to do almost anything to prop up the ailing British Empire.

My thoughts, for what their worth.

true, without those bullshit like commissar order, it's likely to see more red army desertion on earlier stage of war; I doubt there would be 10 million Slavs joining, let along German had the equipment to arm them, notice the poorly armed Romanian/Bulgarian and Italian divisions, at most German could put up 50 or so reliable slav divisions.
If things went bad for the Soviet, West would certainly like too bring back the status quo, so Western powers would likely to pressure Germany, impose embargo, lend-lease Russia, threatening war..etc. As we all know German has very little fuel reserve, an oil embargo would grind the operation down to a complete halt within 6 months, providing German wasn't able to capture Soviet oil field. Though Stalin would most likely sue for peace at this point.