optional rule for hills: hull down: Duck and Cover

As the rules stand now, level 2 and 3 hills do exactly the same thing: they allow you to ignore level 2 terrain. Because of this, there is no reason to climb to the top of level 3 hills.
To simulate the increased height advantage, assume that a hill does not negate area terrain cover’s cover save for cover equal to the height of the hill. The hill will still allow firers to ignore terrain of any depth as far as LOS is concerned. Therefore, a figure on a level 2 hill would still be able to see over level 2 terrain and ignore its capacity to grant a cover save unless figures are actually imbedded inside level 2 area terrain. In such a case, they get a cover save, but can be fired at no matter how deeply they are imbedded.
With this rule in effect, level 3 terrain would allow a figure to ignore area 2 cover terrain.