I never expected to see Bolivia, Nigeria and Mexico (!) on the list given that these nations seemed pretty unassuming. Mexico in particular, because of its close proximity to the US, which is less prone to interventionism and the like ITTL, still has a commitment to ensuring stability in the Americas.
Mexico has an outsized sense of nationalism, both because of its early 20th-century revolutionary history and because it's right next door to an Anglo great power, and still remembers the last American intervention even if it was a century ago (especially since it had only been
half a century at the time the Mexican nuclear program began). Sure, the US is a good neighbor
now, but why not have a deterrent just in case?
Bolivia is one of the two leading states of the Andean region, an indigenous-dominated republic in a sea of criollo/mestizo societies, and at the time it began its weaponization program, its neighborhood was still a bit rough.
The Union of Nigeria is one of the great powers.
In any event, none of the current nuclear-armed countries have used their weapons in anger - the two countries that have done so are no longer nuclear powers - and by now they're considered increasingly anachronistic, but for the moment everyone has their reasons for keeping them.
Also, on AnalyticalEngine's world map (Part 1), I noticed that there are different types of autonomous designations, such as federated states, dominions, vassals, and autonomous areas. How much autonomy/sovereignty do each of these areas have?
It varies depending on the terms agreed between the regions in question and their sponsor countries; there's no set standard. A lot of the nomenclature also depends on the historical relationship between the parties and the identity of the nominal head of state (especially for dominions) rather than the amount of actual self-rule. In general, the autonomous areas, which are actually part of another country rather than having a looser affiliation, are less independent than the others, but there's plenty of overlap.
I was also surprised that Ethiopia, Egypt and the South African Union don’t have them but I guess in the former two’s case it’s because they rely on hydroelectric power .
Also no would mind if I add some video game ideas I had for MR (including some malevied versions of OTL video games)
Actually, the reason why Ethiopia and Egypt aren't on the list is that I forgot to put them there - you can safely add them. The South African Union never invested in a nuclear program because its conflicts and threats have historically been mostly internal, and because it's a loose confederation that doesn't have a large federal military force. It does have nuclear plants as part of its power grid, but no weapons.
And go right ahead - you may also want to check out
post 6413 if you haven't done so already.