I can't believe it took me this long to work it out, but I've finally cracked the mystery of why ArmA 2's terrain, while being nearly photorealistic, feels unnatural.
There's no dead ground.
I'm not talking about huge valleys or sprawling basins, because as we all know, there's no shortage of those. No, what I'm talking about is the smaller-scale stuff - the stuff yours truly would seek refuge in with his mates in a contact. Drainage canals, creekbeds, culverts along the sides of the road, berms, craters, fissures, erosion channels... the list goes on. Nowhere in the entire game world - and now I think about it, nowhere in that of the first game, either - do I recall seeing any of these. Considering that ArmA 2 is regarded a sim rather than a shooter, and also considering the heavy emphasis on infantry combat, wouldn't you think that the infanteer's favourite forms of cover would be included from the outset?
I'd gladly sacrifice a few forests, truck-sized boulders, and locked buildings to see these included in ArmA 2. Don't even start me on the gates and doors, though.