I wish ID software would do further single-player installments in the series, and Quake Champions was a boring hero shooter so it did not count.
It is also one of my favorite games of all time, as I like both the monsters and atmosphere. My favorite levels in the game are actually the base levels at the start of each episode as while they are "high-tech" looking, they are also grimy and rusted out places only populated by surgically-lobotomized grunts and enforcers. Somehow, the base levels of Quake 1 are more interesting-looking and ominous than those of the Strogg from Quake II and IV.
One of my favorite mods/map packs for Quake I is Alkaline and I use the Ironwail engine.