"Man, other than infinite height enemies, blood brightness being too high by default, numerous mapping errors throughout Doom 1 and Doom 2, forced weapon switching in deathmatch, a maximum of 4 simultaneous players, 320x200 resolution being blurry, the irritating MIDI glitch on The Inmost Dens and The Catacombs, that blindingly bright invulnerability effect, invisibility spheres being a detriment 99% of the time, an automap that was passable for 1993 but is nearly worthless these days without mods, the inability to add custom sprites easily in vanilla, the lack of any dedicated deathmatch maps, the lack of splitscreen, and a whole bunch of other aspects I'm not too crazy about, this game is PERFECT!"
(lol it took me time just to think of all these nitpicks.. none of them prevent it from being a fantastic game.)