WMG / Command & Conquer: Red Alert 3

Ackerman is an android in all campaigns

The Japanese make him increase the American's war efforts against the Soviets to keep the pressure up on their closest enemies in the Soviet campaign, and cause him to launch superweapons against the Soviets in the Allied campaign in the hopes of one or both factions being destroyed. Ackerman still being present in the final level of the Soviet campaign can be explained by Tatsu secretly trying to use the Allies to avenge his father's death after his own surrender.

Krukov really was planning to backstab Cherdenko

It would certainly fit with his arrogant nature, and further explain why he basically sabotages the player by "requisitioning" your credits in Von Esling airbase in the Soviet campaign. The only reason we have to believe that the assassination attempt on Cherdenko was faked was (a) he survived, and (b) Dasha told us it "must have been". Even further, it would be perfectly fitting for a Soviet campaign to have various paranoid leaders scrambling to the top with as much backstabbing and skullduggery as possible.

Had there been a Red Alert 4, it would've featured FutureTech as the new faction and new main antagonist, with the Empire either being assimilated into the Allies, as a reference to the post-WWII occupation of Japan, giving them the advantage of their technology, or gone entirely.

FutureTech themselves are the main antagonists in the campaign for the soviets, and also have a presence in Yuriko's campaign. This, combined with the Challenge mode being essentially their version of a campaign seems to mean they were going to be built up as the main antagonist, and given that the Challenge mode is all about stealing information about the units from all three factions, it's likely that the potential units that a hypothetical FutureTech faction would have were going to be entirely new units that combine features from the units of all 3 factions or are enhanced versions of them.

The reason why the Soviets are limited to just Russia unlike how they had Cuba, Iraq, and Libya, on their side back in the original incarnation of the Third World War in Command & Conquer: Red Alert 2 is because the Allies took over the those countries in this timeline.

The tiny problem with this is that they do have Cuba - they're launching the strategic imploder Kirovs from there, remember? Just because non-Slavic accents aren't represented among the Soviet lineup doesn't preclude the presence of countries aligned to them.

---