Honestly, as much as people complain that the 3rd Int is too strong and unrealistic, the Entente is so much worse at meeting plausibility checks, but usually gets a pass because of the political biases of those making the criticisms. For some reason we're supposed to believe NatFrance can plausibly survive as a solely colonial power in North Africa without constant revolts and a totally unstable government, and that Canada is powerful enough to do stuff like invade the US.
This isn't even going into stuff that was flat out removed or will be like the A.O.G. in China, or the SRI being in the south opposing a Pope-led Italian Federation.
As for economics, Kaiserreich basically handwaves that everything works , protectionism, free trade, a regulated capitalist market, market socialism, a planned economy, Syndicalism, etc. are all considered viable by the game because it is first and foremost a game. There are very few exceptions to this, and they tend to be country specific, which usually is because of a dev or some pre-existing lore on the country.