In my (limited) experience, having mostly Xel'lotath enemies tends to be quicker because the zombies are both slow and flammable, giving a one-hit kill in levels with a torch, which also lets you past bodyblocks quicker. The black guardian is also very easy for green, though I think phase 1 timing is tighter. On the other hand, you get restore health + stamina really late, so it might still be slower because of walking.
Hey there! I was learning this game about a year and a half ago but had to stop because I didn't have time with uni. I'm now just coming back and relearning/practicing and routing, and hopefully should get a practice run done and submitted soon.
Nice to see there's more people (even if only a couple) on this game than last time I looked!