I'll chip in. I have played all of the SR series games until the pixels wore off, but I've been leary of 1936 until there was something to actually see, kick, and bite (eg, playtest).
I'm also a long-time Hearts of Iron player, and I saw how hard it was in HOI for the devs to implement simple things like "realistic" carrier-carrier battles and invasions (something SR has had its own problems with in the past). Still, I can't help but compare 1936 to HOI. They cover the same historical period and have the same meta-strategic approach.
Re: Long wars. Vietnam was at war with France from 1946 to 1954. They were at war with the US from 1956 to 1975.
The US has been in Afghanistan now for 12 years.
In the 17th century, Netherlands and Sicily maintained a de facto state of war for 335 years
So while I agree about how the AI can get carried away with long unended wars, it's not true that this hasn't happened in the real world. In SR, this game mechanic has been one of the main reasons I've found playing minor countries in Central Asia to be unenjoyable - I have to make nice with Russia or find myself in an unwinnable war trying to conquer everything from Vladivostok to Moscow. If I forgot to turn off "moving capitals", I'm playing whack-a-mole for 20 game years chasing the Russians around.
In previous incarnations of SR, I've seen crazy, unrealistic straight lines drawn across defeated nations with no regard whatsoever to ethnic or cultural boundaries. Maybe ethnic/culture boundaries (or even just provinces) are too much to ask of the engine at this point, but to me it makes a lot more sense than treating India, for example, as a big homogenous chunk of territory with a demarcation like Korea 1953.