It did occur to me, when looking at the mission editor, that the density of destroyed buildings and kit around La Trinite was very high. It certainly isn't making life any easier for the convoys.
I'm also not convinced about the effect it has on the atmosphere. Lots of towns were trashed - why is La Trinite special in having lots of vehicle wrecks? If that is where the main battle was, you wouldn't use it for your trading ground - too much unexploded ordnance for a start.
Even putting that aside for a second, think about the geometry: by necessity the armoured wrecks have to go around the circumferance, which means you need an awful lot to make them look it dense. Better to give up on that unattainable objective, use fewer and let the player's imagination do the rest. I liked the blocking off the road to the west though, because it was done at both ends. That's the sort of thing that really contributes to atmosphere.