I would like to present some of my thoughts for a no-WW2 TL. I think it is hard imagining the 40s and 50s without a major war, so some input and critique for my thoughts is very welcome.
scenario: Germany in 1932/33 is taken over by a Reichswehr Junta. Instead of the insane rearmament of OTL, we see a much slower and sustainable rearmament. This includes laying the foundations for a functioning military-industrial complex. Germany still manages to gain some of the lost territories, but slower and in a genuienly diplomatic way. Somwhere in the 40s Austria joins Germany.
1) Colonial Unrest:
It is an often repeated trope that without WW1 colonialism would have lasted longer. That is true to an extent, but in other ways WW2 froze some colonial conflicts.
Without WW2 imho it is not unlikely that:
a) India erupts in the mid to late 40s. A huge popular uprising against British rule. If the Torys are governing, we might see a very bloody attempt to stop the inevitable. Churchill fantasized about this in the 20s already, without WW2 we might see it happening.
b) Assuming that the Communists still win a Chinese Civil War in the late 40s or the early 50s:
France is still going to have a big problem with the Viet Minh. Given the WW2 performance of France, I don't think it is outlandish to assume that a Soviet/Chinese backed Viet Minh could draw France into a very bloody quagmire. France would eventually lose.
c) In the Middle East tensions might also erupt in the 40s or 50s.
2) Nuclear Weapons:
If we don't have the "Jewish Physics" idiots in control, imho Germany is a frontrunner for getting nukes. If the German military budget is growing in the 30s, but the Regime is not willing to enlarge the army too much, we might see a lot of of money for blue sky schemes.
And without driving away a ton of talented physicists, the Germans could capitalize on their scientific lead in that area.
Is it likely that Germany might develop a nuke in secrecy, that is ready in the mid to late 40s, without parallel programms in Britain or France?
And where would Germany test a nuke?
3) Stalinism without WW2:
The crazy militarism was not sustainable forever. At some point the economy would have collapsed due to military overspending, planned economy inefficiencies and autarky. Is it reasonable to assume, that a slowly dying Stalin would start a huge war, to save his slowly unravelling system in the 50s?