The worst I came out of a stack in Burma (and I bagged to Australian fightes to boot) was loss of 3 fighters, 3 tactical bombers and a strategic (the latter to the AA Gun.)
To make India a cake walk, it was totally worth it.  7 planes for 1 NO, 1 nation, and no resistance in the south from anything (including Australia due to lack of planes.)
However, I do ahve to say, my DOWs are generally round 3 since most of my opponents know it’s futile to stack in Burma against me.  That means on Round 3 the NB/AB drop on Hainan/Kwiang or whatever that territory is down by FIC.
The nice thing about waiting an extra round is the +6 ground units, +2 aircraft and +3 transports you can bring iwth you to drop on India - castrading those poor ANZAC planes.  Means there’s a 10 IPC Australia, 0 IPC India, no Australian meatshields for America and an America sitting there going “uh, oh shit. Where did my allies go?”
As for the Russians, there was no IPC in my mind for them.  It’s Mongolia they lose (and the what, 6 infantry?).  Fine.  I welcome the attack.  It’s only ever been an issue in one game and then only because Japan’s attacks everywhere on the board went to hell and America focused almost entirely on Japan - capturing Tokyo on round 11 (just to give you an idea of how bad the dice were for Japan.)
Previously, Germany’s main goal was to take London.  The whole idea of Japan holding off one round is to stop America from pulling a “jerk move” like landing Bombers there.  Legal, but hardly realistic.  I’ve done it myself - don’t get me wrong, but it’s still a jerk move in my mind, like Germany blitzing out to take Africa (which they would lose immediately after) in classic for the M84 win.
Lastly, I think I said this as well, I agree, you have to pretend Sea Lion. This transports are not wasted, they serve you well dropping units from both W. Germany and E. Germany into Karelia each round. (10 Transports is 20 Infantry a round into Norther Russia.  Russia cannot stop that AND a push on the East AND the possibility of an end run in SZ 100.  They’re still HORRIBLY underpowered, though much better than Larry usually makes them. IMNSHO.)
Final thought, I still think the whole panic was centered on London.  I think Calcutta attack, which was developed not so long ago, still have so many people saying “impossible” that it would be premature to do anything to stop it.  I do it, I do it almost every game, and the games I did not do it, were usually the ones I lost - Japan does not earn enough to match the Americans AND deal with China, Russia and India.
In fact, I believe those Russian infantry are only an issue IF you don’t get Calcutta early.  Since now you have a three front war.  If Calcutta is gone, Japan actually has a chance to win the war - in my mind.