Coming off of the main game, I decided on shifting the difficulty down for anxiety's sake. I think it was this choice, combined with RoE's addition of the classic, powerful double-barreled shotgun, that made playing the expansion a breezy diversion, even if it was basically DOOM 3 in a condensed form, give-or-take a few new weapons and powers. Story-wise, it's a handful of contrivances to justify returning to the setting, but honestly, who cares?