The point of the Karila G1 and Caucuas G2 is to cripple Russia by R2, Its a bit of a gamble but it you get the UK BB/ tran they have no ability to land in B1 and by B2 you should have a large stack of tanks in Berlin plus 3 bombers and 2-4 fighters if you were lucky with the karil attack. Russia will not have produce more than 16 units by the end of R2 and if you hold the cuasuas in G2 or I2 they will only be able to produce 6 units in R3 which is really hard to mount an effective counter attack with in R4
With Russia in shambles by G3 they can start to look towards the UK US threat and leave Moscow for I-ties and Japan well leaving a small mop up force of whats left of your infantry and 6 or so tanks because the fighters and bombers can always fly back for the last blow…
The I-ties could throw 4 inft and at Moscow a turn to weaken it in I3, I4 but not in full attack pulling back once the inf are lost and replace them with ones made in causuas if it is held in R3 well building up an Afrika army
I would suggest in that in J5 and I5 a sapping of Moscow to weaken it for taking in Germany in G6 because the extra 6 IPC would come in handy for Germans war effort against UK US and if they don’t have to commit huge force but only administer the knock out punch most of their forces could be in the Atlantic and France and Afrika and not Russia.