What alternate history ideas you wish they were used more often?

[Catsmate]

Personally, I would say that it is more likely that Esperanto ended up being implemented by a techno-fascist regime (technocrat + fascist) that believes that other languages are both inferior to Esperanto and contrary to scientific effectiveness and efficiency. Only that type of regime would be ruthless and determined enough to carry out an imposition at gunpoint of a language that probably not even members of the ruling elite themselves speak.

Perhaps, though historically there was more interest on the left, before Stalin in '37. Maybe a victorious Republican Spain? Esperanto was popular amonst Spanish anarchists, some groups socialists and the Catalan nationalists.
Alternatively as a common language for a supra-national federation (I used it thus for EuroFed in the EDCverse, leading to genre of paranoid British films and TV portraying the Esperanto Institute as a sinister organisation with the objective of world conquest).