To me, most of the main game, maybe besides the updated starting area, always felt a bit too “peaceful”.
Sure, there are a view abandoned cars, burning tanks, military camps, etc., but outside of certain mission locations most of the map, even in more densly populated areas like Östervik, feels simply empty and looks too “pristine”, at least in my opinion.
Compared to that HImfjäll feels much darker and messier.
Crashed cars, much more emergency vehicles, roadblocks, makeshift barricades, boarded up windows and doors, cars and buildings riddled with bullet holes, burning houses, civilian bodies, etc. .
I have to say that personally, I really enjoy the darker, messier and more detailed look of Himfjäll and the updated starting area and think the devs have really improved in terms of level design.