Why? Stalin was a good leader, but he wasn't irreplaceable.
I'm assuming that there is a protracted power struggle between Red Army, NKVD, senior members of the Politburo, and other factions. Perhaps I overestimated the effect of cutting Stalin off, as this didn't bollix things completely in OTL 1953. However, OTL the Soviet Union was largely at peace when Stalin died; here there are Germans at the door. Possibly Moscow gets captured, further mangling leadership, although I didn't insert that in (TBO admittedly makes the whole 'post-soviet transition' more likely by having Moscow fall and the Soviet's backs to the wall, although it makes it less realistic by having the postwar government be all happy-shiny).
The Russians largely manage defenses anyway, after all its their homes on the line. However, with less of the competent leadership on the field and more of it concentrating on power struggles, perhaps with the NKVD being purged as well, they won't do as well with taking advantage of German difficulties. Also, with Hitler knocked out of it, a delayed Final Solution, and a marginally less overbearing leadership, the Germans have to face fewer partisans in the Ukraine and the Baltics than OTL, allowing them to concentrate a bit more on regrouping from losses.
As for the France invasion, I figured that, since the Soviets are doing worse they'll cry even more for a full second front - in OTL, Churchill opposed this, but in this TL Roosevelt overrides. In FaT, an invasion of France was accomplished, here I made it succeed and added a second invasion, probably the larger of the two - the soldiers that OTL go for Sicily instead go for Southern France, with an additional landing on Sardinia and perhaps Corsica for more ports and less available Axis aerial support. In any case, Italy is much less of a threat than Germany. A southern France landing is probably the wisest choice in support of a northern landing - Even without a Sicily invasion, the Axis navies are already largely finished in the Med. by late '43, and France is the required base for a real strike on Germany proper (the problem with the "soft underbelly" Italy is that the Alps block it off from Germany).
There are advantages and disadvantages to an early landing. The big disadvantage is that Germany hasn't faced round-the-clock bombing as much or for as long yet, and has easier resupply and more troops available. On the other hand, the Atlantic Wall is less complete than it would be in the next year, and the Allies will still almost certainly have air superiority, if not necessarily the complete dominance would it had by later 1944.
What makes them Communist in name only?
First, its a Junta led by members of the Red Army, generally communistic but less so than a civilian-led administration, and not following much of a Stalinist or Trotskyist dogma, rather taking a more traditional dictator's view of "do whatever has to be done to survive". The Red Army took a severe beating from Stalin's purges in the 30s, and the officers who aren't bootlickers recognize that Stalinist communism, at least, is problematic. I kind of want to have Rokossovsky (sp?), an officer who OTL was released from a gulag due to the desperation for leaders, to have a substantial role as well.
Second, promoting the revolution too much will make those capitalists enemies, when they can just as well send you money. A less ideologically dedicated government will tone down its message, largely to keep Lend-lease and trade with the US, Britain, and others. Especially postwar, the leaders will recognize that trade
What I imagine is that, postwar, you'll have something like the USSR under Lenin's NEP, or Deng's China - outwardly praising Marxist-Leninism, but more "flexible" towards market solutions and not badmouthing its neighbors, or spreading the revolution a la Trotsky. Perhaps a less crazy version of the Myanmar junta, or something more akin to OTL fascist states, would be an even better comparison.
What made FaT so compelling was that, at first, it was a very plausible TL, showing us our world, but through a mirror, darkly.
True, although eventually it went completely off into "Murphy's Law as TL".
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