The average metal suite is actually far less homogenous than Reign in Blood, and they have a distinct rise and fall of tension that carries throughout the entire suite. There are even individual songs that pack more variety into less than a third of Reign in Blood's running length without sounding disjointed. Even thinking of Reign in Blood as a single musical unit, I don't finish it thinking that it has taken me somewhere or provided any sort of experience, not in the same way that Ulver's Bergtatt a suite of similar length, does. It can only do one trick, and it does it over and over until I lose interest and listen to Forbidden or hell, an earlier Slayer album, instead. It's not awful music, just either severely underdeveloped or severely overextended and either way outclassed by its predecessors.
And I actually have heard death metal covers of "Angel of Death" that sound better than the original.