Interesting thoughts…
Some feedback…
The only way that the Allies can prevent a link-up on G2 is to suicide the initial UK navy, plus some UK1 build navy, all of it moved to/placed in SZ6. Without that block, the Baltic fleet sails to SZ7 unopposed. Even if UK (or USSR) places 1 ship there to “block”, Germany takes it out with AF, and moves the Baltic fleet to SZ7 in non-combat move. By the time UK or US is in a position to actually attack the German fleet with Allied navy, the link-up has already occurred.
You could, theoretically, have Russia suicide their AF against the Baltic fleet to weaken it, then use the UK navy to block, forcing Germany to use up some of THEIR AF. You could also suicide the UK AF into the Baltic fleet (though in this case, the AC and 2 FIGS are present, making losses minimal, basically 1 round of hits before the RAF is gone). This of course assumes that Germany did NOT Sea Lion in G2, in which case there is a 62% chance (including tech roll) of UK not building a darn thing, EVER. But, if Germany does not Sea Lion, at least SOME of that Baltic fleet is going to end up in SZ7 with the sub, BB and tranny. Not the strongest fleet, but with UK lacking a bomber and 2 figs, and with Russia being down a pair of figs also, and with UK also possibly being down their initial UK fleet plus some build material… well now that fleet isn;t looking too bad. UK is not going to be attacking it again until UK3, and the US needs to get there first…
As for the UK sailing their fleet into the Med…
Balkan and Ukraine figs solve the problem of taking Egypt without the German med navy, sealing the canal to UK on UK1.
And as for the South African IC…
If UK did all it could to stop the fleet link-up, as you advocate, then UK can ill afford to spend half of their money on an IC in South Africa. They are lacking an AF and a Navy, with Germany having a loaded carrier, a BB, and a tranny within striking distance of UK, plus the remainder of their massed AF (probably another 2 figs and a bomber, allowing for Egypt moves) within range of London. That is a first round attack roll of 24 (4 kills) against a UK that no longer has any figs for defense and spent half their money in South Africa, and the rest blocking the German Baltic fleet.
Your Russian strategy deserves a LOT of thought though. Taking out the cannon fodder from any German attack is a hell of a viable concept. It slows Germany more than you posted. Germany will not have any G1 purchases of INF available before G3 for Ukraine or Bel. It will be G4 before the surviving G1 purchased INF can reach Caucuses/West Russia. And, with the Baltic AC build, THAT is only 8 INF in combat range on G4, less losses from strafing or from re-taking Ukraine or Belorussia.
Germany CAN make some initial advances due to less-than-maximum stacking and spreading their forces, but they still maintain the ability to counter any German attack in R2, and wiping out the lion;s share of any German gain, as well as the potential for gains in the rounds to come, for quite some time. It does create a bit more of a dead zone in mid Europe than would otherwise have occurred with a total R1 INF build, but the trade off appears viable on first review.
DEFINITELY deserves further review.