Units don't appear to fire on radar pings that are in range. They also have extremely short view ranges, even when on a hill, or similarly advantaged. This results in all engagements being pretty close range, having longer ranged units doesn't seem to be of much help beyond being able to have more units shooting things at once. The rocket turrets are particularly objectionable, as you basically have to set them up well behind the front lines for them to benefit from their range. You can't actually set up a defensive line at a cliff and fire down on attackers with impunity, because they wont see them, nor fire into the blind using radar for target acquisition.
I got myself a sentinel turret and set it right at the edge of a hill, then put five of the long range turrets back behind it and that seemed to work pretty well, but spotting is horrendously costly as currently designed. You can build artillery centric units, but they're going to have to face plant the enemy to see them anyway. The game would play entirely differently with FOW off.