i'd say end it at 2001 at the absolute latest. enough time to account for for changes, without going into the war on terror.
I don't see why we need to cut the game off as it's approaching today: If you start the game in 1946 or even somewhere like 1962 (that's when I'd start it, so Africa is mostly newly decolonized - like how Victoria II starts soon after Latin American independence), the world of 2015 is going to bear little resemblance to that of today. How often does your Victoria game in 1885 look like the real 1885? Putting in scripted events for things like 9/11 or the Arab Spring would be as silly as putting in a Franco-Prussian War scripted event in Victoria II - Paradox doesn't make its games that way anymore.
If I were in charge, the game would go 1962-2100, and have a general pattern something like Victoria II. A first phase of sorting out the problems left over from the last war, revolutionary upheaveals, then the game settles down for a bit. But then automation starts breaking down the industrial system, nations in the "Third World" begins to catch up and rise to Great Power status, global warming and resource shortages start to bite, and by 2100 you're playing a totally different game than in 1962, just like with Victoria. I'd get a little silly with new ideologies and technological shifts.
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