Though your plan seems to have all the answers I think that there are a number of problems. Most importantly Hitler's idealogy would not really allow for a very long delay in an assault against the USSR. Ultimately the East was always his intended direction, not the rest of Europe. Also, Hitler struck the USSR at an opportune time. The T-34, and to a lesser extent KV-1, was only just coming into mainstream use, imagine if the bulk of the tanks initially engaged by the panzer divisions were T-34's instead of the variety of lighter (eg. BT-series) tanks actually faced. In my opinion, the panzer divisions would not have really upgraded their tanks, or have developed the Pz. V-VI models, as these were primarily designed to counter the Soviet tanks. This means that the bulk of the panzers in use would be pz III versions, whose 50mm main gun was pretty abysmal against the heavier Soviet tanks.
Also with the purges diminishing, if there was no repeat then the longer the German attack took to materialise the more organised the Soviet command structure would be.
Lastly, I believe that if Japan went to war with the USA Hitler would also declare war as long as he was still at war with the UK and it's empire.
And, from memory, Col.Gen. is right, the Blitzkreig name was not a commonly accepted military term at first. The Germans thought more in terms of Schwerpunkt and Aufrollen, ie. local superiority to create a "puncture" in the enemy lines, followed by exploitation to the rear and to the flanks of the enemy positions.