Besides making it harder for an enemy to get to you, what good is an Elevated Firing Position? I see no benefit unless the enemy is Lumbering.
From the SRD:
Elevated Firing Positions
If a unit is more than 6” above an enemy it makes a shooting attack against, and is within 15” on a horizontal level, it is said to be in an Elevated Firing Position.
If the enemy unit has the Lumbering trait, then it will suffer an additional –1 penalty to its Armour rolls against shooting attacks made by units in the Elevated Firing Position.
From the SRD:
Elevated Firing Positions
If a unit is more than 6” above an enemy it makes a shooting attack against, and is within 15” on a horizontal level, it is said to be in an Elevated Firing Position.
If the enemy unit has the Lumbering trait, then it will suffer an additional –1 penalty to its Armour rolls against shooting attacks made by units in the Elevated Firing Position.