User blog comment:SArchangel/Altverse Concept: Greek Superpower/@comment-3993996-20160307015005

Firstly I would recommend you focus on your China project before moving onto a next one.

Secondly, Bulgaria will always have tried to annexe Macedonia. The Balkans has always been a hotbed for nationalism and Bulgaria would never have been content without Macedonia. Serbia also became the Balkan regional power partly through its links with Russia - such links would still exist. Greece being neutral would mean that other European powers would suppress its development in the name of maintaining the balance of European Power which was a key goal for many European foreign policy makers at the time. Britain had a vested interest in the Mediterranean and would have stopped Greece from building a navy to rival its own unless Greece got help from a rival power.

Thirdly, the White Movement in Russia would never have retreated to Greece. They would have continued to fight the Bolsheviks who were a tiny force in 1917 (they retained power mostly through sheer luck and brutality) so it was very plausible that autocracy would return to Russia. Many of them were also based in Eastern not western Russia (hence why whites controlled Outer Mongolia). In the extremely unlikely event they did flee they would also go to one of the Russian Slavic satellites in the Balkans (Serbia/Yugoslavia or Bulgaria) not Greece.

Fourthly, the Greeks probably wouldn't have "won" the First Battle of İnönü. The Greeks were better equipped, but they were unprepared and retreated only because they didn't want to waste large numbers of men. The First Battle of İnönü was really small scale, and was only "won" on a propaganda level. The Greeks still would have had to deal with large Turkish resistance and would not have been supplied by Allied powers if they were neutral (the Allies never supplied them anyway). Turkey wasn't supplied by Britain or France but by the Soviets who would supply them regardless (their relationship was mutually beneficial especially in the division of Armenia). The Greek Genocide was also well underway before the Greco-Turkish War having been started in 1913.

Fifthly, there would have been huge resistance to a Greek conquering of the Balkans. Yugoslavism (which was never strong in Croatia and Slovenia) would have prevailed over what would be perceived as Greek Imperialism (at least the Serbian, Croatian and Bosnian languages are somewhat mutually intelligible for a start), nevermind Serbian, Albanian and Bulgarian nationalism all of which have always been historically strong. There was massive resistance to the Nazi and Italian occupations of Yugoslavia which was never stable in the first place - the Greeks would be seen in the same light as the Germans and Italians. That's just the nationalist resistance as well - nevermind the fact that royalists (i.e the Chetniks) and communists would oppose a Greek invasion and would actively fight it (in WWII its likely Belgrade would still face the iron fist of the Red Army and red partisans) as would foreign powers like Britain who had friendship treaties with Yugoslavia (who, being near to British colonies in Egypt, was more important then landlocked central European Czechoslovakia which was of no tactical value).