Good thought experiment you have going on. Most of the time doesn’t Germany fully commit to Sealion on G3 by either doing a direct G3 attack on London or landing is Scotland, right? If that is the case, they can see that on R1 and R2 the Russians have only purchased naval units (meaning a theoretical 26 ground unit deficit vs. max defend build) why do Sealion? On Italy round 2, you could use the Italian air force to clear the blocking Russian BB in the Baltic Sea and then amphibious assault Leningrad. Without those R1 and R2 ground builds, I would think Russia would be relatively easier to take down. Especially when done in conjunction with Japan doing a max push into Russia which is what I think I would be doing with them if I saw the Russian build naval forces en mass.
Just my thoughts on what I would do if Russia made the builds you describe.
I tend to agree, it would be easier to take Russia first, would that be dangerous leaving UK alive, if USSR provides them a fleet to protect their builds. That seems like it gives both US and UK quicker and stronger strikes against Europe then would otherwise occur. I suspect even with no real land unit builds until turn 3, that Moscow could hold until turn 6 or 7, maybe longer maybe not.
That gives the allies a 3 turn window of opportunity to get entrenched in Europe and put some heat on Berlin/Rome. Key to this opportunity will be whether USSR can knock down the German factory on W. Germany turn 4…That severely limits what the Germans can build in Europe for defense. I could see USA knocking it down turn 5 if recaptured, and UK grabbing it turn 6…etc. Keeping Germany with only 10 unit builds turns 5-8.
Oh well, its just a crazy Russian navy idea. Not sure I will ever try it. You are basically screaming, take me! take me!. Certainly a magnanimous move to spare the British player and allow him to play sea lion free. I’d like to be that nice guy.