The figure head of SiOC has to be Stalin, but he was definitely no slouch when it came to spreading the revolution. The Soviet union invaded Finland, The Baltics, Romania, Poland, Mongolia, Iran, and Xinjiang. they also gave significant support to the Chinese, Korean, and Spanish revolutions. interestingly enough, all those invasions are basically universally denounced by Trots. Regardless, they represent the USSR invading practically every country it bordered and every important socialist revolution of the time apart from the Greek partisans.

So as I see it, what else could they have done?

Declared war on the United Kingdom in the 1920s? obviously a disaster, once the Soviets lost in Poland, I don't see how anything like this could be held as viable, but you can also blame Stalin for losing in Poland, if you wish.

Declare war on Fascist Germany sooner? the Soviet Union wasn't ready to fight Hitler in 1941, let alone the 1930s. They had no border with Germany, and Poland refused them when they did consider an invasion of Germany, but I guess you could argue the war would've gone better earlier when Germany hadn't fully remilitarized, and didn't have GPMGs, or Czech tanks or Romanian oil.

Spurn the Capitalist world and refuse to do partnerships with Germany and the USA? Frankly, the partnerships and expertise they received from the USA in the 1930s were critical to defending from the Nazis. We've seen how socialism develops when you try to replace capitalist technology with the revolutionary enthusiasm(which the soviet union wasn't immune to either, see "Soviet Tempo") and the result is backyard furnaces and backsliding.

Edit: And trade with Nazi Germany? Cotton for Heavy Machinery is not, I think, a morally bankrupt deal. Oil for Heavy Machinery is more concerning, but again, the Soviet union was not ready to fight Hitler even in 1941. if you embargo a country, there can be consequences. just months after Barbarossa, Japan declared war on the United States because of an oil embargo against them.

Yes, the Soviet Revolution was eventually crushed and ended in ignominy less than a century later, and it was precisely because they couldn't overcome their being under siege for their entire existence, but I still don't see how a rapid war to defeat foreign capitalism is given as a viable suggestion.