I didn't get into too much detail, other than a little back and forth with Richard about the feasibility of magnetic mines to screen off the Royal Navy. When I wrote this I had recently read Robert Forczyk's We March Against England, which paints a very optimistic appraisal of Germany's chances of a cross-channel invasion in the OTL, but since then the more I've read indicates that this is a bit pie-in-the-sky. Britain knew about magnetic mines even without capturing the ones Germany dropped on land, so obviously that alone won't ensure a successful invasion. So then it comes down to whether Germany can build enough small escort vessels and anti-shipping bombers to beat the Royal Navy straight up in the Channel. The more I think about it, the more it seems far-fetched. Germany was never anywhere close to Britain in naval strength, and even if Germany had started planning this in 1919, I doubt they could have built up a large enough force without the British knowing.
So maybe your Russia strategy is the ideal one. Have you considered an earlier date for Barbarossa, like August or September 1940? Or Germany invades Poland in May 1939, France in September 1939, and the Soviet Union in May 1940? It seems time is the critical factor in any invasion of the Soviet Union. Germany needs to get the job done before the USA starts attacking in the Mediterranean and the West.