(Note: Beforehand, Stalin keeps all the brilliant generals, and doesn't have the bad 1941 Soviet army leadership)
a) The pre-1937 Soviet military leadership is often terribly overestimated.
b) The post-1937 Soviet military leadership is often terribly underestimated.
But I'd say that Zhukov, the foremost post-1937 commander, was for all his shortcomings better than Tukhachevsky, the foremost pre-1937 commander. Tukhachevsky had some nice ideas about modern warfare, but the Soviet army never suffered from a lack of theoreticians.
5- Stalin is afraid of Nazi Anschluss and invades Poland with 3,000,000 troops to act as a buffer state. France, Britain, Germany, Italy, and the US condemn this move. In fact, Hitler was planning to invade Poland, but was still building up forces.
Firstly, why the hell would anyone apart from Mussolini be afraid of the Anschluss? Secondly, how is invading Poland connected with it? And thirdly, why the hell invade a state if you want it to be a buffer state? An invasion would naturally have the opposite effect.
As a matter of fact, Poland was
already a buffer state, and that is one of the reasons the Soviets did NOT, as a matter of fact, try to invade it.
Aside from that, I have only to add that such a move would make no sense whatsoever, and would greatly conflict the general Soviet policies of the era. Its not only a risky venture (meaning something that Stalin would almost never allow, not before 1945 anyway), but also an extremelly spontaneous one and a one bound to
unite all the potential Soviet enemies. I can't imagine it being done without first securing support from either France or Germany, and as both countries wanted Poland as an ally and were more than a bit wary of the Soviet Union I can't really see them accepting this back in 1938.
7- Soviets declare war on Germany.
*blinks*
The military aspects are more than a bit implausible as well. The Red Army's problems were never as much in the leadership corps as in logistics; they would simply be unable to advance to western Poland and fight off the Germans with such ridicilous ease. That is simply out of the Red Army's realistic reach. The Polish military was also quite formidable; I really doubt that it would be brushed aside so quickly and easily, at best the Soviets could advance to the Curson Line, and even then I'm not sure if the Poles would invite the Germans in.
The war's escalation also apepars quite ridicilous. Czechoslovakia is bad enough; it may be considered a cunning flank maneuver, though the Third Reich wasn't nearly as fond of these as the Second Reich, and rightly so. But Romania is just plain wrong. I honestly can't see either side wanting to waste their resources there. It is totally irrelevant to the war itself.
So, just screw it.